Rotom-N
Typing: Electric-Ghost -> Electric-Ghost
Ability: Infiltrator
50/50/77/95/77/91 -> 50/50/97/135/97/111
New Moves: None
Explanation: Alright, no new moves, no new typing, slight buff in stats; this is basically a standard mega evolution besides the ability, which I withdrew from its pokedex entry, which states that Rotom "infiltrates into other appliances". Nothing much to say, really. Infiltrator is a great ability, especially when you have 111 speed and access to volt switch.
Rotom-Fan
Typing: Electric-Flying -> Electric-Flying
Ability: Aerilate
50/65/107/105/107/86 -> 50/95/127/135/127/86
New Moves: Rapid spin, Recover
Explanation: Electric-Flying stays; all rotoms should probably keep their typings. The ability is Aerilate because I'm going to attempt to make all the rotoms ate-themed. This gives it an unblockable rapid spin (and it's a fan, soo....). Recover is wanted on all the rotoms because it somewhat makes sense and they need it.
Rotom-Frost
Typing: Electric-Ice -> Electric-Ice
Ability: Refrigerate
50/65/107/105/107/86 -> 50/95/127/135/127/86
New Moves: Ice beam, Recover
Explanation: So Rotom-Frost's only changes are really ice beam, recover, and refrigerate. Ice beam was missing from this thing because of game freak's trolling capabilities. Recover is there for all of them. And the thing gets refrigerate, because what do you see? A REFRIGERATOR.
Rotom-Mow
Typing: Electric-Grass -> Electric-Grass
Ability: Foliate (-ate version of grass type)
50/65/107/105/107/86 -> 50/95/127/135/127/86
New Moves: Energy Ball, Recover
Explanation: The main changes to this are Foliate and Energy Ball. Energy Ball is there for a reliable grass STAB while Foliate is there for the -ate abilities pattern. Note that all the rotom forms get special normal type attacks in uproar.
Rotom-Heat
Typing: Electric-Fire -> Electric-Fire
Ability: Flareate (-ate version for fire types)
50/65/107/105/107/86 -> 50/95/127/135/127/86
New Moves: Flamethrower, Recover
Explanation: This is pretty much sticking with the trend, word for word. You've got the unchanged typing, the -ate ability for its type, the unchanged stats, the 90 BP reliable STAB move, and recover.
Rotom-Wash
Typing: Electric-Water -> Electric-Water
Ability: Hydrate (-ate version for water types)
50/65/107/105/107/86 -> 50/95/127/135/127/86
New Moves: Rapid Spin, Scald, Recover
I did something different for this thing. Hydrate, typing, and stats are still sticking to the trend, but the move pool (hue) is what separates it. Rapid Spin because of the spin cycle, and it spins things around; Scald instead of Surf because it was the next best thing since a washing machine can't surf.