Wondered about the capacities of the stadiums, so thought I'd share here for anyone else wondering.
Chelsea v LAFC
Mercedes-Benz Stadium, Atlanta
Capacity 71000
Attendance 22137 (31.2% full)
Botafogo vs Seattle
Lumen Field, Seattle
Capacity 68740
Attendance 30151 (43.9%)
Palmeiras v Porto
MetLife Stadium, NJ
Capacity 82500
Attendance 46275 (56.1%)
EDIT to add today's game
Flamengo v Espérance
Lincoln Financial Field, Philadelphia
Capacity 67594
Attendance 25797 (38.2%)
These are just the worst ones of course, some matches have done ok.