Mixed

Back squat training elicits greater improvements in lower limb dynamic strength on a nonspecific strength test (45° leg press) compared to front squat training in recreationally trained females, while both variations produce similar hypertrophic adaptations in the lateral thigh.

If your goal is maximum strength, prioritize the back squat. It allows you to lift heavier loads, which translates to better strength gains on other exercises like the leg press. If your goal is just muscle growth in the quads, either squat works equally well, so choose the one you can perform with better technique and less joint pain. You do not need to force yourself to do front squats if they cause shoulder discomfort; the back squat will get you the same muscle growth.