Manually move return of rome units to AOE2 DE

I’m making mod reskin and making new civ for AOE2DE. I also want bring back the old units from return of rome unit to AOE2 DE as new civ. Can someone tell me how to manually doing that? I can’t figure out how to change the unit animation ID in ROR so they don’t overlap with AOE2 DE. Also I can’t find the json file or what file log the ID for each unit skin and animation. Any help on this would really appreciated.
Thank you everyone in advance.

C:\Program Files (x86)\Steam\steamapps\common\AoE2DE\modes\Pompeii\resources_common

Maybe a bit late but I made a mod a while ago adding all the ROR dataset units to the vanilla AGE2 dataset.
Hasnt been updated since then but feel free to check out in the Genie editor how it was done.