I found the following users who may fit your language exchange criteria:

Username	Date	Post Link	Relevance	Offered Matches	Sought Matches
u/shinkaishinkai	2020-10-29	Post	`5`	English	Portuguese
u/uktobrazil	2020-10-14	Post	`5`	English (Native)	Portuguese
u/sophienicole77	2020-10-24	Post	`5`	English	Portuguese
u/ben--grimm	2020-09-06	Post	`5`	English	Portuguese
u/myself404	2020-09-11	Post	`5`	English (C1)	Portuguese

Please feel free to comment on the above posts to get in contact with their authors.