However the boon has taken effect, Gon isn't going to say much. He'll simply nod, and rather aburptly his body will just...

Fall over. Zangetsu should see his spirit fine- as it is, Peridot will feel a gentle nudge against her consciousness asking permission to hitch that ride. Until she agrees, he's just kinda...awkwardly floating there.

But once she does agree, he seems to vanish. And Peridot won't actually feel anything, until-

"Auh...I, the man Gongenzaka...Think this may be working? ...I believe I am seeing through your eyes...?"

Welp, there he is, and there he'll stay for the ride.