Orthaheel strap slippers good 4 overpronation/bunion has deep heel counter. Like clogs but back of heel tiny bit higher. As good as shoes?

Depends who you ask. The negative is you have better balance and stability in a closed shoe vs clog type or open back shoe.
Orthaheel. There is more to overpronation than adjusting the heel. They are not really shoes. Real orthotics can compensate for biomechanical deficiencies and nothing makes bunions go away except surgery. Bight the bullet and go see a professional . Your podiatrist will be glad to help and further debunk some more myths for you. Good luck.