In previous generations (when TM’s were consumables), if a parent could pass down an egg move and knew a TM move, it could pass down the TM move to the Child if it could learn the move, despite the move not being an egg move. (This was likely done due to the limited or difficult methods of acquiring TMs). They could’ve made the same thing true for TRs, but I don’t know how it would pass it down without knowing the move, unless you got 1 egg before using a different TR. :P
Superpower then wouldn’t pass down due to Torchic’s inability to learn it. Just a guess , though. I’m too lazy to prove it. :P