By resetting data from debug menu, the Translation feature won't be switched off, but the function will be stopped. So the Show Translate Button toggle and the feature are not synced.
You can switch Language > Show Translate Button off and on once, and the feature will work afterwards.
To open debug menu, tap 10 times on the Settings button
App stops showing Translate button for selected messages. The feature won't work until switching the feature off and on again.
App detects the state of Translation feature toggle correctly.
All iOS Devices