marilli
With you
Nah, they definitely do run Sheer cold, it's Lapras's only way to avoid getting walled against fat Pokemon like Snorlax, Ferrothorn, and the like. Thunderbolt is used, too, but especially the AV set you will see Sheer Cold be used. Your experience may make you think there's less of them than there actually is, because in many games it goes unused, especially against an offensive team like you posted.
Ferrothorn is also definitely good. It beating Mimikyu and Lapras is huge, and so is forcing these Fire-move using Pokemon to be brought. Darmanitan and Togekiss always uses Fire moves, but neither can switch into Gyro Ball. Thus, Snorlax and Dragapult often have to as well, and if they are brought vs a Ferrothorn on a team that otherwise doesn't have obvious Fire-move coverage (Togekiss, Darmanitan, Rotom-H, etc.) you will always assume it has Fire move and switch out. If you were wrong Ferrothorn will win anyways so it doesn't matter, and if they did have a Fire-type move like they should, then you made the right play.
One thing I think I believe strongly is that Ferrothorn should never be your primary sponge into Rotom-W. This basically has been the case like, ever since BW OU. If it is, then it will start every game vs it burnt, and you won't be able to win with it even if you get rid of their Fire-type coverage.
Ferrothorn is also definitely good. It beating Mimikyu and Lapras is huge, and so is forcing these Fire-move using Pokemon to be brought. Darmanitan and Togekiss always uses Fire moves, but neither can switch into Gyro Ball. Thus, Snorlax and Dragapult often have to as well, and if they are brought vs a Ferrothorn on a team that otherwise doesn't have obvious Fire-move coverage (Togekiss, Darmanitan, Rotom-H, etc.) you will always assume it has Fire move and switch out. If you were wrong Ferrothorn will win anyways so it doesn't matter, and if they did have a Fire-type move like they should, then you made the right play.
One thing I think I believe strongly is that Ferrothorn should never be your primary sponge into Rotom-W. This basically has been the case like, ever since BW OU. If it is, then it will start every game vs it burnt, and you won't be able to win with it even if you get rid of their Fire-type coverage.