Why would be illegal for company to want to hire whoever they want to?
In order to be non-discriminatory, a person has to be hired according to their ability to do the job, without consideration to their ethnicity, age, skin color, etc. A language can be learned, so requiring someone to speak specific languages to apply is non-discriminatory.
What about modelling? Do those rules apply also there?
https://www.refinery29.com/en-gb/2018/11/218140/choco-media-...
It's my understanding language requirements are acceptable - it's a skill required to complete a job and language isn't a protected class, much like age, race, sex, sexual orientation, etc. is in many jurisdictions.