Cyrillic locale

Hello.
Faced with a little problem: hass.io doesn’t show cyrillic symbols in configuration files properly. I need to use them to specify friendly_name customizations for some entities.
I know that it is Alpine problem, since Home assistant instance living in Docker alpine container, but I’m not able to find how to set locale in Alpine. Actually, there is no locale at all.
Maybe someone know a solution?
I know that I can use smb to edit configs and get rid of the problem, but I prefer ssh.