@Ivan219 Speaking as a host, incoming payments may be by wire transfer, and those seem to be free (and airbnb states so in the settings of payments). Other options for hosts (I have never tried them) are charged.
Speaking as a guest, the final amount that was charged was higher than the original booking on the website, so it seems that guests are charged, but it may vary depending on their bank offers. But that shouldn't bother you as a host. 😉
// "The only person you can trust is yourself"