That's not a simple reskin. The Ubese uses one 3D model (body including head), while the player model has a separate head and body.

There's some issues with disguises getting your appearance stuck, but it's the easiest route.
Get KotOR Tool running, open the item file for the Dark Jedi Master Robe:
Kotor II > BIFs > templates.bif > Blueprint, Item > a_robe_18
Now go to the Properties tab, double click the row at the bottom with the * to add a new property. Pick Disguise under Property Name, find Sith_Assassin_01 under Subtype, press Add, press Save and save to the main override folder of the game. Done, try it out.

Oh, it's you! I've seen your mods. I guess you'd know whether or not it's simple.

I've tried using the KotOR Tool, but whenever I do it, it says it didn't detect the installation anywhere. I've manually gone into the paths and selected the directory, but it still gives me the error and locks me out of the functions.

If it's too much trouble to figure this out, that's fine. I appreciate your help either way.

It's me! :D
See if my guide helps:
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=779622644

You'll probably also get an error from "check for updates" (that's no longer available), you can turn it off under options -> other

I think I've decided this reskin attempt is more effort than it's worth (especially since it seems the outfit I want to use covers the head too), but I'll hold onto this in case I decide to swap something else around. Thank you very much.

By the way, thanks for the recolor mods. My T3 looks beautiful in blue.

Although, now that I think about it, there are some things I could do. The main reason I want to swap out the jedi robes is because the cloak on them, especially on the jedi master robes, always feels a little too big and awkward on my player model. I can't find any versions of those without the exterior cloak, so I might have to just swap it with something else.

Alright, good luck and feel free to ask for more assistance.

Originally posted by Effix:

It's me! :D
See if my guide helps:
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=779622644

You'll probably also get an error from "check for updates" (that's no longer available), you can turn it off under options -> other

This worked! Now to see if I can swap models around.

Okay, it seems the next confusing step is figuring out how to find the parameter information for the Echani Light Armor (for example) so I can swap out the model* and tex* info in the appearance.2da file with its info.

Sometimes I just browse through all the textures that are near what I'm looking for but Gamebanshee can tell you which template you're looking for:
http://www.gamebanshee.com/starwarskotorii/equipment.php

Next to that you need to know a bit more about how appearance.2da works, this will help:
https://deadlystream.com/topic/4725-detailed-information-of-2da-files/

From the above you can see that the Echani Light Armor should be a model in the C column (-> PFBCM/PMBCM) and from opening the template a_light_07.uti you can see that the texture variation is 3, always 2 digits so 03 -> PFBC03/PMBC03.

The icons work a bit differently, but also with that texture variation number. They work with those class types on that overview on deadlystream (you can also look up the base name of the icon in baseitems.2da). In this case you have a class 4 item and texture variation 3, so the icon is ia_Class4_003 (this one always has 3 digits).

Most of the time you don't really need to change anything in appearance.2da, you just put another model or texture in your override folder with a name that it expects/points to.