I’ve got the same issue as this user, but in my case, the screen is full in English. Despite, I defined my local in French: LANG=fr_FR.UTF-8 and my system language is fr_FR, the update plymouth screen is still in English. I also used the “dracut -f” command to regenerate the initramfs but it doesn’t work. I know that the translation strings are translated in French. So what’s wrong ?
sudo plymouth-set-default-theme -R bgrt (if you use default fedora plymouth ) and after that dracut -f or first check plymouth-set-default-theme what is default plymouth and do sudo plymouth-set-default-theme -R bgrt if is default bgrt