Does Flame Orb work in Misty Terrain?

Question

I was wondering that because MT cancels statuses, but what if it's forced by Flame/Toxic Orb?

Answer 1

After a few frustrating attempts of people activating Electric Terrain first turn, I can conclude Flame Orb does not work under Misty Terrain.

Calyrex is holding Flame Orb in this replay

Source

However, Terrains obviously don't work on not grounded Pokemon, so if you give a Flame Orb to a Flying Type or a Pokemon with Levitate, it will still get burned even in Misty Terrain.

Answer 2

Pokemon can be statused as long as they aren't gounded.
As you can see in this replay, Obstagoon wasn't burned, but Corviknight was, since it wasn't Grounded. This also works with other status conditions (except confusion, from Gen 7 onwards), as seen with Dragonite getting Poisoned. It also doesn't have to be the orbs, using moves like Toxic will work too.

Source: This and experience.
Hope I helped :)