Um Orkonaut, Staryu isn't Psychic type, he's pure water.
Ok Iota, I want you to start by firing a Will-o-Wisp - at Machoke! We're trying to activate guts Sigma, so if it looks like its about to miss, try to be hit by it, even if it wastes your action. If it hits nicely though, run up to Staryu and Thunderpunch it.
Next, I want Iota to Disable Trapinch's bite so it can't attack later. Meanwhile, Sigma, I want you to pick up Staryu and Vital Throw it to another island, following if possible.
Iota, finish up by firing another Will-o-Wisp at Trapinch, while Sigma uses Revenge on that distant Staryu.
Iota: Will-o-Wisp (Machoke) ~ Disable (Trapinch's Bite) ~ Will-o-Wisp (Trapinch)
Sigma: Thunderpunch (Staryu)/Get hit by Will-o-Wisp ~ Vital Throw (Staryu) ~ Revenge (Staryu)