Rotator cuff/scapular stability exercises

Around 9 months ago I had grade 2 ac joint sprain. Not looking for medical help but I still find I have achy pain when shoulder pressing heavy and often on lat pull downs my rotator cuff gives out before my lats on the affected side. I’ve been doing many IR and ER along with upper back exercises for around two months now but not sure what to do about it at this point. It’s really affecting my lifting especially pushing and i’m barely making progress. Pretty sure it can be blamed on my stabilizing muscles so i’m wondering if anyone has any exercises that helped them with shoulder pain at all? Thank you, any response is greatly appreciated