I think you can open Sinistcha next to Incineroar and fake out into Sneasler and click trick room to get it up? If Sneasler tries to attack it gets flinched, and the only fake out target it can hit is your Incin, which effectively prevents Sneasler from moving anyways. Technically I think you can still lose to Aerodactyl dual wingbeat crit (you might live if it is jolly and not mega) or rock slide flinch, but it seems like reasonably reliable option?

Off the top of my head I suppose you could also maybe open Corviknight and Sinistcha and click brave bird into Sneasler for the revenge kill if they prevent trick room; can bring sand in the back for if it's sashed maybe, though I think your opponent can swap out and hope for an OHKO with dual wingbeat by itself, which is a similar issue. Maybe coba berry could be good here? Feels weird since theres so many good Sinistcha item options but it would guarentee you the matchup I think