Try hamstring and piriformis stretches....and kale.
With my right leg down and lean foward,My right sciatic hurtsBut when sitting with left leg down and right leg on coffe table and lean foward not much pain at all
Odds are you have piriformis syndrome in the right glute. and the cure is not to stretch the piriformis but to forcibly contract your glutes because the muscles are weak (total homo). https://www.michaelcurtispt.com/driving-buttock-pain/