So I encountered (and tested) something quite interesting on showdown. As we all know, having the ability mold breaker (or teravolt, w/e), ignores the opponent's ability. Therefore, you can hit a pokémon that has levitate with earthquake. Now what I encountered is something that has to do with this mechanic.
Whenever a pokémon with the ability mold breaker goes for a move that fazes the opponent out into another pokémon, this will also negate the ability of the pokémon
on switch-in. What this means, is that a pokémon with the ability levitate takes
all hazards on the field upon switch in. Hard switching a pokémon into the mold breaker mon does
not activate this mechanic, only if the moldbreaker mon goes for a fazing move. This even goes to the extent where, if a poison type gets fazed in by a mold breaker mon, it will get rid of the toxic spikes. I tested this in this replay:
http://replay.pokemonshowdown.com/gen7ou-649443653 . Now, I am not completely sure whether this is a bug, or whether this also happens on cartridge, and am not able to test this myself. It could, however, be very gamechanging to have a levitating pokémon take spikes/t-spikes/webs. I ask that someone tests this on the cartridge to see how this mechanic works there, and if it does turn out to be a bug, to have a developer take a look at it.