So, is Epic Armageddon it's own stand alone rules?
I know the original trilogy characters and vehicles well enough.
Ok so. Epic Armageddon (a warhammer 40k 6mm spinoff for those not in the know).
Has its own complete ruleset and quite active community who have kept the rules available for free online with GW's blessing ever since the company stopped supporting it somewhere in the 2000's IIRC?
You can find the full game rules here:
https://tp.net-armageddon.org/rules/And a list of the current "tournament approved" army lists here for reference.
https://tp.net-armageddon.org/do note that there are
no unit creation rules here. New army lists are still created, tested and balanced actively by the community though. But there are no fast and hard systems for it. My clone wars lists are absolutely a shot in the dark. I've played quite a bit of Epic, but not with or against all types of armies and still not nearly enough to have a perfect sense of balance, so I'm constantly tweaking those lists as I re-consider their appropriate stats and point costs, and some community vets on the taccom discord are helpful enough to give pointers at times as well.
My personal approach has been to see what role and niche a unit fulfills in the star wars universe and use 40k units with similar battlefield functions as a starting point. My b2 super battle droids have the same armor save as space marine terminators for example. The B2's are the toughest infantry unit during the clone wars, so they get the highest stat there. Are they equally as tough as 40k terminator marines? Impossible to say. the weapons in both universes are so very different and fiction will depict either as near indestructible or easily killed depending on the needs of the story so I don't worry about it too much.
In my experience its a mistake to try and directly copy over whatever starwars legions does for their abilities, but it can still be a good point of reference. When two unit types in the same army seem very similar at first glance, it can be useful to see what legions does to distinguish them for example.
I would also add that Epic Armageddon is not a "hero hammer" game, unlike so many of its warhammer compatriots. Characters are a part of the game, but they are added to other units of infantry or vehicles and add one or two attacks and some special rules at most. Named characters with extreme stats who dominate the spotlight of the battle are just not a thing. Amazingly even such vaunted titles such as "space marine chapter master" are often boiled down to one or two special rules they provide to their host unit and that's all.
As for force powers, 40k of course has similar stuff with psychers, but again depending on their focus they might provide a simple special rule, or an extra attack types or two.