Netgender

Netgender is a gender that is expressed more frequently online than in real life. It can be used by itself or combined with other terms, e.g. netboy, netgirl, netnonbinary, etc.

It is the opposite of rerumgender.

Flags
The netgender, netgirl, and netboy flags were designed by Mod Hermy of Pride-Flags on DeviantArt on February 17th, 2017.

The color meaning for the netgender flag is because blue is associated with "online".