GRU airport enables international-to-international pax to simply get screened and onward to their deparing gate, regardless of Terminal.
GRU T1 & T2 have a connector that allows pax to be international-airside, without having to go through Immigration & Customs.
There is a paid rest area for international pax with small cabins/beds and showers if the layover is too long, operated by a private company, international airside located, between T1 & T2.
Cheers