Help - Hip Assymetry and Unflexible/Cramping when loaded.

I have a very noticeable difference in my hip flexibility tighter right vs left. I really realized this is a problem last month when doing 2-handed shield casts with a 10lb club while in the shin box position. I could do 13 shield casts in 30-seconds left to right vs just 3-5 right to left while struggling to avoid hitting my back on the back swing. Also, I do a Slam Ball program which is all about deep squatting and in the rock bottom position for 60 seconds that right hip tends to cramp after 40-50 seconds. Never the left side though.

Can you suggest any routines or

Particular exercises that would help with range and mobility in those hip areas?

I added 2 photos showing this particular exercise that exposes this severe assymtry and limitation. Photo 1 on left - is the left to right more mobile/no cramping and photo 2 - is right to left right side limited range, tight and cramps on prolonged deep weighted squats. Thank you for any ideas I am committed to overcoming this but regular stretching isnt working