Update: Okay appearantly, the character transfer did mess some things up. After the transfer, my helmet had the mod "Jump Jets Mod" installed (a mod I didn't even know exists), which caused my character to jump insanely high. The weird thing is, once I put it out of my helmet, it is no longer compatible with it (its only compatible with chest armor).
Another strange thing: My steel axe now has the metal chains mod installed, which, normally, is not compatible with an axe, and additionally it has this mod "Liquid Nitrogen Mod" installed, which I, again, wasn't even aware of his existence. Probably some things which are only accessible via the creative menu? Idk, but yeah I figured out why my character jumped so crazy - problem solved, I guess
I uploaded some pics if anyone is curios:
https://bilderupload.org/bild/d1ac81231-20220603202404-1
https://bilderupload.org/bild/946e81279-20220603202459-1
https://bilderupload.org/bild/313f81293-20220603202506-1
https://bilderupload.org/bild/247481308-20220603202528-1
Pregen6k, only mod I use is a no-crosshair mod (no crosshair when aiming with firearms)