What can be done to minimize the appearance of prominent brow bone after hyaluronidase? (photo)

This is not a good place for filler. The most complications occur right there. However, from what I can see in this one photo you may have prominent bone. That ridge needs to be removed surgically. This takes about 90 minutes and will address loose skin as well.

Supraorbital ridges like yours are usually result of natural bone formation. It is unlikely that this may be result of filler? If these are true bony prominences they will need reduction/shaping with a burr. This can be achieved through an open brow lift incision. In person consultation with a board certified plastic surgeon would give you an opportunity to be properly evaluated and informed about possible treatment. Good luck.

Based on your post photo that the dissolver injected dissolve your normal subdural and subcutaneous tissue. Best option would be nano grafting or micro fat grafting or the combination there of under ultrasound guided injections fee $5000-$10,000 to virtual consult with.