You should be able to give regeneration to units in Advanced Genie Editor

Context: I’m making a Star Wars The Clone Wars mod, and for Droidekas I had the idea to give them the self-shielding unit trait, so they regenerate. that didn’t work, probably because its from star wars galactic battlegrounds. So please, bring that self shielding feature to the game or add an ability to give units regeneration.

Funnily enough, you couldn’t give units regeneration in aoe2hd through genie without making them a hero - and on release I don’t remember being able to give units regeneration, but I may have had erroneous testing; HOWEVER you now CAN give units regeneration in the genie editor, I’ve done it at least twice now
Do make sure that the unit has the regeneration task in the tasks menu, look at camels for example since they all have this for maghrabi camels

You can give regeneration in the scneario editor with the modify Attribut effect.