Why is she turning yellow?

It’s hard to tell in this picture (pic 1) I also removed quite a few of yellowed leaves so there isn’t nearly as much.

I did some research and I believe it’s either nutrient deficiency or overgrowth. I ruled out overwatering because I rarely water her and when I do, it’s minimal. I’ve had this plant for over two years and it’s quite obvious that it needs to be repotted. The only reason I haven’t yet is because the same issue happened to another pothos of mine (pic 3) and I repotted it in well draining soil and it turned into “picture 2”

If anyone has any advice on what I should do and what went wrong with the first pothos I need it lol.