Just enabled Discover in my Google App and what I see
View attachment 267258
1. Open your
Google App, tap on top right corner on
your account.
2. Select
Settings, and then select
Language and region, you can find Discover Language there.
3. If it is not there then get back Delete your account activity/ Interests. Make sure that App and Web activity in ON.
4. After this Discover Language option should appear and set it according to your preference.
Hope this'll work.