If you're using Mimikyu to set up, there are a few Quick Guard users you can choose from to protect him from things like Taunt and Fake Out. Crobat and Talonflame come to mind, but Phermosa, Passimian, Lucario, Pangoro and Scizor can all learn it too. It just depends on what you're building and what you need to compliment your core.What are some good teammates for Mimikyu? I'd really like to find a good way to use it, but the thing's extremely frail and dies within two or three turns, one of which I need to use to set up.
Tapu Lele does this too, and does it passively, but other than that, they don't have much synergy.
And all things considered, Mimikyu has pretty decent survivability thanks to Disguise.
(Note: These do not factor in the first hit absorbed by Disguise. So the 2HKOs are 3HKOs)
252+ SpA Celesteela Flash Cannon vs. 252 HP / 0 SpD Mimikyu: 126-150 (77.7 - 92.5%) -- guaranteed 2HKO
252 SpA Gengar Shadow Ball vs. 252 HP / 0 SpD Mimikyu: 134-158 (82.7 - 97.5%) -- guaranteed 2HKO
252 Atk Muk-Alola Gunk Shot vs. 252 HP / 4 Def Mimikyu: 106-126 (65.4 - 77.7%) -- guaranteed 2HKO
252 Atk Garchomp Iron Head vs. 252 HP / 4 Def Mimikyu: 110-130 (67.9 - 80.2%) -- guaranteed 2HKO
Those are some big threats. AlolaWak is still an issue, so pack someone who might can take care of him and his ilk. Maybe even your own AlolaWak!
I'm just tossing around ideas after running a few calcs. Let us know what you try and how it works!