if items frames are teleported to the player and the player is at an angle the item frame will teleport off the block and go at and the angle but the hit box will stay the same spot even if faced on another block but the hit box still needs to be supported by a block
You rotate the entity, the nbt data specifies which side it has attached to, so that won't change at all.
What happens if you teleport one out of that block spot (a couple of blocks away)?