Eshan seems to be a Hindu name, and the Islamic sites seem to have confused it with Ihsan/Ehsan, which means "good deeds", "beautiful manners".
There is no Arabic name that sounds like Eshan. The way some Islamic sites spell it, as عشان, is actually an Arabic slang word that means "for that reason" and no one would use it as a name.
According to some sites in Hindu sources it means "The Lord Vishnu", which they say is the creator of "the other gods". Since this meaning is not acceptable Islamically, Muslims shouldn't use it.
However if in some sources or language Eshan means something that's not against Islamic teachings, then it can be used as a name, since in Islam what matters is the meaning.