State_translated on openweathermap

Openweathermap gives me a nicely translated forecast when using the HA dashboard and setting the desired language in HA GUI, however when I try to do templating I see some tranlations missing, i.e.
{{ state_translated('weather.openweather') }} currently renders as ‘слънчево’ which is Bulgarian for Sunny, but
{{state_translated('sensor.openweather_weather') }} rednders as ‘clear sky’. Same goes for text based forecast sensors , like sensor.openweather_forecast_condition.
Can anybody help me find out if this is a HA GUI issue or an integration issue?

Bumping my own question, I just noticed that when the weather outside is changing, the service response language is also changing, so while everything looked fine for ‘sunny’, rainy whether is not properly translated. I’ll try to look for the localization strings in HA and/or the API response on openweathermap itself.