I would distinguish between where your leg naturally falls, and how effective it is. Work on effectiveness, and don’t worry about position.
I have two friends with distinctly asymmetrical foot position. Since I’m primarily a dressage rider, I register that one of their feet sticks out too much rather than that one is too straight ahead. But it’s the same thing you show.
For both, it’s a known problem in the hips or pelvis. One also has mild scoliosis. The other has a diagnosed hip anomaly but I have forgotten the name.
I expect you have an asymmetry at the hip or pelvis level and it sounds like you already know that. I would suggest a sports physical therapy appointment to get a clear sense of what your limitations are, and then off the horse exercise targeted to ameliorating this.
You need to be able to squeeze, to two point, and to move your leg around for different aids. You don’t need to have your toes pointing right off the horse for this, like a 9 year old pinching with the calves over cross poles :). Toes pointing straight out is not an inherently functional jumper position. But being able to squeeze for aids and stay up in two point matter.
PT may be able to give you exercises or you can continue on to the various good suggestions given above. But first find out what your functional limitations really are. It changes things if you have scoliosis or an uneven pelvis, etc.