Thanks for your answer.

@Brecht Van Lommel (brecht) so if that sounds like a good first contribution, I would like to try :D !
Can we also add the possibility to combine the different PBR channels together into the same image (e.g. metalness in RBG, and smoothness in A)? or is it going to be too much changes?

A total overhaul of the baking system seems very nice, and I particularly like the idea of using nodes, that seems powerful, that solves the UI mess the baker can be, and Blender could provide some "baking templates" for Unity, Unreal, etc...
However, reading the conversation, a total overhaul may be slow to agree on and implement?

What would be amazing for game development is the ability to export the cutout animations in a file format that we can use in most game engines.

So, I am not sure what is happening. Was the bug resolved as part of T54862? or is it considered intentional?

Unity allows that, and it shows "--" when the values are different. It is quite handy to be honest.

oh sorry, it seems that I succeeded in clicking twice on the "create task" button and I created a duplicate task, is there a way to delete this one? Thank you :)