You keep using that word... and I'm torn between suspecting you simply don't know what it means, and being appalled by the implication that you think your morals are absolutes.
Ah, no... it does not.
Morality is fundamentally subjective.
"Good" and "Evil", "Right" and "Wrong"... these things depend on the views of the speaker. The cultural, societal, and legal norms they were raised in, their education, and their own experiences and feelings. They're subject to change over time based on changes in society and culture, personal views and experiences, health, and more. Sometimes they change rapidly, and other times it takes generations. The point is that they are not constant over time or between individuals.
Case in point, there are cultures on this planet where various entries on this list are NOT considered evil.
The view that human trafficking and slavery are "evil" is a relatively recent cultural development that's still a long way from universal acceptance. Until the mid-19th century, they were not only considered socially acceptable but necessary for the maintenance of society in even the most enlightened ancient cultures and modern nations like the US and UK. The last country to ban slavery (Mauritania) didn't ban it until 1981, and even then they didn't actually criminalize owning slaves until 2007. There are estimated to be somewhere between 12 and 30 million slaves in the world today. It's still widely practiced despite being illegal in much of central and southern Africa, India, Pakistan, most of Southeast Asia, Russia, and western South America.
Human cannibalism likewise used to be widely practiced, socially acceptable, and even religiously significant in many cultures. There are religious and tribal groups like the Aghori and Korowai that still consider cannibalism socially acceptable and practice it.
Same story with paedophilia. Standards for what ages are acceptable vary quite a bit between cultures and religions and have likewise changed over time as well. Fairly recently we had a former judge from down south who ran for office and was dogged by a scandal involving different attitudes towards acceptable ages in the same culture and country. He had been involved with girls in their young teens, which most of the country found abhorrent but which that region found more acceptable. I don't want to get into the religious side of this for obvious reasons.
For drug dealers, it depends a great deal on what drug they're peddling. Until recently, selling marijuana was frowned upon. Now there's a growing number of states and countries legalizing the sale of marijuana. It no longer carries the stigma it used to. There were, likewise, times when things opium, cocaine, and heroin were socially acceptable to sell and to buy. The famous fictional detective Sherlock Holmes mirrors the attitudes of the time, in that he was a recreational user of cocaine and morphine and this is treated as being quite acceptable. It's not now, but it was back then.
There are a number of countries where sexual assault is still considered, if not "acceptable" then "excusable" under various circumstances. Even in allegedly enlightened countries like the US we're still struggling with groups who feel there are categories or conditions under which rape is acceptable.
Killing another person is one of the best examples. Whether or not this is "evil" is SO subjective that people can have multiple, conflicting opinions on the subject based on incredibly specific circumstances. You'll find people who, in the same breath, will suggest that abortion is evil because it ends a life and that those who practice it should be put to death for doing so. Opinions are incredibly divided over what constitutes acceptable circumstances to kill in self-defense or just cause for war.
There really are no moral absolutes in this world.
There aren't even moral absolutes within a single culture, nation, state, city, or large group of people.
Morality is a flexible abstract that we bent, twist, fold, spindle, and mutilate to fit our circumstances, views, and beliefs.
I'm honestly not sure even you know what point you're trying to make...
There is no objective evil. People who do things others see as evil believe themselves to righteous, or justified, or that those things were necessary, or simply don't acknowledge that the things they're doing are wrong at all because they have different standards.
There's that word again.
To be objectively evil would mean that, regardless of an individual's views and beliefs, that something can be factually demonstrated to be wrong. Things can't be objectively evil because morality - the concept of good and evil itself - is fundamentally subjective.
You yourself acknowledge with your very next sentence that the Nazis believed they were in the right doing what they did... which refutes your premise that they were "objectively" evil. If they were objectively evil, then their evil is a demonstrable and irrefutable fact. They would see themselves as evil precisely the same way their adversaries did. They didn't... which means it's subjective. There are, distressingly enough, groups of people out there today who argue that the Nazis did nothing wrong. Even if you want to argue that they're brainwashed, that still means the perception of morality is can be changed situationally.
To be frank, the Nazis could've been swayed by reason easily enough. The whole reason their party came to power in the first place was the crushing weight of war reparations the German government was obliged to pay, the ensuing hyperinflation of their currency running their economy into the dirt, and led to fears of a communist uprising. The militarism was an economic stimulus. If both sides had sat down and talked before the shooting started, the entire war could've been avoided by taking remedial action to save the German economy.
Because a technologically-advanced species is, by default, going to be a social animal. You can't pass down learned knowledge from one generation to another without a social framework through which to do it. One of the cornerstones of social species is empathy: the ability to understand and/or vicariously experience the thoughts, feelings, and attitudes of another. That means evolution literally neurologically hardwired them to respond to attempts to communicate.
Those are not social animals, so that's kind of a BS attempt at an example case.
A social species is going to have language of some kind. It may not be something intelligible to us initially, but it will exist as a quantifiable property that can be studied, analyzed, and eventually replicated to communicate. Bees communicate through dance and pheromones. Whales sing. Elephants vocalize in infrasonic ranges, and cats in the ultrasonic. Hell, cats are intelligent enough that they have a separate language in the audible range for speaking to humans. We learn easily enough to intuit what our dogs want from their behavior and vocalizations. It's not an insurmountable problem.
It really does make all the difference.
Macross, like Star Trek, acknowledges that a conflict with a hostile power will occur because both sides believe themselves to be in the right. That they are doing what's necessary for their people and nation. This does not make them evil in and of itself, it merely means they have a different perspective and that peace can potentially be achieved by finding common ground. Gundam is a pessimistic version of this, where peaceful resolution CAN be achieved (and humans are literally evolving psychic empathy to help it along) but the universe is run by crazy people who refuse to have a meaningful conversation with anyone who doesn't share their views 100%. The moral ambiguity is crucial, as is the point that most combatants are not bad people... just people in bad situations.
Star Wars exists in a universe of moral absolutes. Fundamental drives are categorized by knowledgeable force users as explicitly and unambiguously good or evil. Dark side users seem to be quite aware they they are in fact evil, and rejoice in it with all the subtlety of a Saturday morning cartoon villain. They want to take over the galaxy just because. There's no way for the light side and dark side to reach an accord because destiny is an unavoidable actual thing enforced by a universal fundamental force and they are destined to try to destroy each other, and their users drag the rest of the galaxy into it. There's zero inlking that the dark siders have any actual goal besides despotic autocratic rule for cruelty's own sake and they're literally fueled by hate and fear. The moral ambiguity is superficial because the conflict and the people in it are explicitly divided into Light and Dark, Good and Evil, Right and Wrong.