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

Username	Date	Post Link	Relevance	Offered Matches	Sought Matches
u/itsyveui	2023-08-06	Post	`7`	English (C2)	German, Turkish
u/lusiovdje	2023-09-09	Post	`7`	English	German, Turkish
u/kurauuu	2023-10-01	Post	`7`	English (C1)	German, Turkish
u/exploding_hangman	2023-10-02	Post	`7`	English	German, Turkish
u/herroyallochness	2023-08-26	Post	`5`	English	German

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