I have the same issue, but with German.
I started the game in German because it's my system language (and mother language). I changed the language in game after starting a safegame, and some parts of the texts ingame stayed in German, for example: Nations, nationalities of players, staff role descriptions and injuries.
Tried the following things without a solve: Restart the game, change language back to german and back to english, check game files via Steam Options.
Only thing I haven't tried is a reinstall of the game.
I have the same issue, but with German. I started the game in German because it's my system language (and mother language). I changed the language in game after starting a safegame, and some parts of the texts ingame stayed in German, for example: Nations, nationalities of players, staff role descriptions and injuries. Tried the following things without a solve: Restart the game, change language back to german and back to english, check game files via Steam Options. Only thing I haven't tried is a reinstall of the game.