The renshuu Discord server has a channel where you can chat in Japanese. Beware though that most people that will talk to you there won't be natives though. Afaik here, the renshuu app, doesn't have a place to do that. It could be in one of the forums, but I'm not sure.
If you want to speak with natives though I recommend those two apps; Hello Talk and VR Chat. I use those 2 pretty often and thought they helped me improve my spoken Japanese.
To add onto what リンク said, there also is a Japanese forum (forums -> other languages -> Japanese/日本語), although the last post was 4 months ago so it isn't really active
