If you're working in Blender, then maybe you can export the torsos you need from other digital Lego programs that do have them. For consistency though, you'll want to use the same type of materials with all the minifigs. If you want to use the Mecabricks exported part with another program's texture, you'll need to import the other textures in the shader editor and then you'll need to remap the Mecabricks parts' UV maps to match the other textures -or- rearrange the other texture files to match the MB UV layout.

Only problem is there are minimal selection of parts on like all the websites. Bricklink's stud.io for example has about the same part choses and so does LDD. any other options do you think? (p.s. thanks for the help).

Hmm... well if there's no source art out there, then I'm afraid to say that someone will have to create it. There are a lot of Ninjago fans on here, and there are quite a few minifigs, but most of them are the main ninjas.

You may have already done this, but you can browse through the available official minifigs in the WORKSHOP with File -> Import -> Mecabricks -> Minifigs. Then browse through the Ninjago folders.

If it's not there, then maybe someone has already made a custom. You can search the LIBRARY to see if something turns up. I tried searching "Krux" and found that FlickBrick420 made customs of the young and old time twins. In the description they said you can use the models as long as you credit them.

To use their models, you'll need to open them in the editor and then save them to your personal library. Then you can import them into another model of yours. If you still can't find what you're looking for or you aren't happy with other people's customs, then you will probably need to create them yourself.

I hope some of this was helpful.