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

Username	Date	Post Link	Relevance	Offered Matches	Sought Matches
u/johanesic	2021-01-29	Post	`5`	Russian (Native)	English
u/nikmaos	2021-01-05	Post	`5`	Russian (Native)	English
u/heres_mishka	2021-01-17	Post	`5`	Russian	English
u/10a9ya	2021-01-04	Post	`5`	Russian	English
u/tonylebrom	2020-12-24	Post	`5`	Russian (Native)	English

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