Many islamic scholars consider chess haram regardless of what the pieces look like, although there are differences of opinion on this. If you are concerned enough to want to cover the heads of the knights I would suggest consulting your imam.
For Muslims
I am not muslim, but my understanding is the knight, if realistically presented as a horse, may be considered haram, as a graven image.
There are options to select sets in which the knights lack eyes, which you may find acceptable.
Of course consult your spiritual advisor as necessary.
The question is about playing chess on this site.
You mean that it, according to your religious beliefs, is a mortal sin to look at the stylized knigt symbol? Then I can´t help you. Thank God I´m an atheist...
In islam the knight could be presumed as a idol of worship so it is haram unless covered up so for religious reasons this makes me not want to play chess on your site because i cannot cover my knight. Maybe yall could make a mode where you can cover the head of a knight if the player wants to in settings