How to force English when on the Windows 10 lock screen?
Solution 1:
See this answer by bugs_, works for me: Per app input language Windows 10
You can enable the option:
"Devices" -> "Typing" -> "Advanced keyboard settings" -> "Let me use a different input method for each app window"
Windows will remeber the langauage you last used on the Lock Screen and it will remain the same the next time you log in.
Solution 2:
After doing a bit of researching it seems that this is currently impossible, unfortunately.