Battle Stadium Head
Kecleon, Uxie/Mesprit, Reuniclus, and Chandelure all look like good options. It's also not so much about the lead matchup as just having a backup setter in case your main one dies before getting it up / first trick room runs out and you need more. dedicated trick room teams like yours need trick room, so if there no trick room and you have no setter you're kinda screwed.Yeah, I know, but Porygon2 (my only other readily-available setter) causes an item conflict with Scraggy, and the few other ones I've tried in Showdown never really gave me a reason to lead with them instead of Mimikyu.
The best thing is to have a non-trick room mode for the team, but adding a second setter is easiest in this team.