Ridge and excess volume in recipient area after hair transplant. Any suggestions? (photos)

Many years ago I had hair transplanted to the front of my head. Recently I decided to cut this hair short. It became apparent that the recipient area is "ridged" and volumised, casting a shadow at the hairline in certain lighting conditions. Can this ridge be reduced slightly and the line of demarcation at the hairline be slightly volumised with dermal filler, to give a smoother transition from scalp to forehead? Is filler contraindicated at the hairline? Can FUE help debulk this area? Thank you