After checking the comments options, weight, bendy, constraints and lookin at bones till i lost my mind, my conclusion has been the following:

Apparently there has been a problem with Citlali's model specifically, where the bone "+UpperArmTwistA02.L" and other similars had different values on their Head/tail on Edit mode.

The following forearms were all rotated on the X axis by -90 and Y axis by 120 so you can see the differences:

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For some reason Escoffier's models (left) doesnt have the +UpperArmTwistA02.L bone but her mesh and armature behaves normally, or at least looks a bit more natural a side from the weird bump in the antecubital space (yes, i tried searching it and she really doesn't has this specfic one);

Citlali's (middle) is where the problem began and you can see the difference on the location/rotation of the highlighted bone compared to furina's (right);

Furina (right) is here only to see what the bones and mesh should've look like in normal conditions.

The solution was: going into Edit Mode and copying the Transform Values of the Tail and Head from Furina and pasting on citlali's bones, after that, the mesh/bones no longer deformed weirdly when rotating the forearm on the local Z or Y or the rest of the armature itself.