I feel it in my knees when I lower really bad.
I have a BB, I do dls on leg days so I don't want to do hack squats. Also, my hip mObility is really bad so I can't squat fully.
Put normal DL (heavy) on back day. On legs day start with knee dominant move (front or hack squats) then hips move (RDL or SLDL). Add unlinear work and calf raises.
For mobility try "squat to stand".