Looking for efficient way to make consistent changes on similar models

Hi, I’m making a game, and a large part of it is with characters in the same uniform because they’re henchmen, but with variation between body types so it’s easier to tell them apart. The basic models are all fully rigged and textured and everything, but the problem is that there’s four variations on the uniform (or five, but that one is a simple texture swap), and two genders besides.

Now, with four variations and ten body types like in this chart, that obviously adds up to about 40 separate models. What I’m asking for is a way to make the models consistent across the variations. (e.g., Fat models in variation 1 will be very much the same as in variation 2.)

The models are all the same geometrically since they’re all based on variation 1, but 2, 3 and 4 all have minor additions which means they have to be seperate models, and I’d rather not re-apply UV maps and weight paint and do all that stuff again for the bits and pieces about 39 times (unless that’s the way to do it)

I’m aware it’ll probably be a lot of work no matter what, all I want is to make sure the models are consistent. Thank you very much for your consideration in advance.

Shape keys perhaps. Changing the features that go to the keys, which can then be adjusted and combined.

Deform modifiers might help and those can be applied as shape keys.

The additional geometry could be there, just masked by the mask modifier. Thus, var1 would have all the features of var2, 3, and 4.

Thank you very much for your suggestions, guys. I’ll definitely try those out! I appreciate the assistance.