Did a ship template! In case the paragraph parts can't be read, they're all under the cut! Had gobs of fun with this one, coloring feels easier when everything is on fire... all of that red hurts my eyes while working on it, though. These two are so important...
What draws them together? They have similar interests (philosophy, science, music, etc.), similar ideals (Chronus essentially acknowledged that Asuka understood The Original's intent the best), even similar aesthetics (similar naming sense, as well as doing cool poses neither nerd has any business doing). Those are the things that drew them together initially—and are still things that draw them together now—but perhaps the most important part is how they care for each other through thick or thin, even through 180 years of separation. The time they spent together is now but a drop in the bucket in their now long lifespans, but both regard this time as important to them. Their love, platonic or otherwise, lived even beyond the cruel passage of time.
What stands in the way? THEMSELVES. They are allergic to happiness and self-forgiveness. Both of them are deeply idealistic people whose actions, while well-intentioned, have invariably caused damage to things they held dear. The world, other people, those close to them. And precisely because they are idealistic and hold themselves to high standards, they find it difficult, even impossible, to forgive themselves. Asuka responds to this by isolating himself. Chaos deals with this by denying himself.
What are their good traits? As a ship, I think one of the good things they have is that they are still pretty interested in each other, despite everything that happened and how much has changed between them. Chaos's voicelines towards Asuka are laced with fondness, and Asuka's still trying to understand what his master is thinking. They manage to be on better terms than any sane person would expect, after the White House fiasco. Both have traits that are double-edged swords—Chaos is incredibly resilient, and Asuka is extremely stubborn. If it goes in the right direction, those traits will help them find themselves again (and each other).
What makes them hopeless at romance? The same things as what stands in the way. These two don't have much rizz, but they are each other's bad bitch they pulled by being autistic. So even if they would probably be bad at romancing most people, they simply don't need that with each other. In a way, they understand each other too well to need that. That said, they really need to talk first, before anything. They need it badly, but Chaos is going to skirt around doing this (really talking) like his life depended on it, and Asuka is going to feel bad about the fact he has needs and deprive himself.
Describe them with one trope: Devotion