Its you. Brook looks slightly shorter but a bit thicker. Size doesnt matter in this fight as neither guy has a big advantage.
Normally Spence looks taller (because he is), but not here. Brook looks stockier. Hard to tell because of Spence's clothes, probably just Brook's shoes. Size won't be a factor in this fight.
There isn't much in it but I think Spence Jr tried a few little tricks to give the impression he is the bigger man.
When they're facing off, Brook looks Spence straight in the eye, while Errol look like he's looking up.