well at first, welcome to the forums and yes. its the right place for your question.
so, you want to change uke-tori position in a mod? that is able to do, but a little bit difficult.
u have to change some of the "enage" stuff. i cant explain u directly how, because im not used to change there alot.
but you have no reason to do this. because if youre in singleplayer then just play as uke instead of tori. if youre in multiplayer and youre tori but want to be uke, just go out of the room and enter to it again. if there are only 2ppl. u will be uke then.