You can have any name you want on an ePassporte Electron card within the character parm's, which btw, are set by Visa not ePassporte. If 20 is all that is allowed, then that should be the same on any Visa card.
I would recommend using your real name for acceptability reasons. You might have a hard time using it if the name on your card is Scooby Dooby or something like that.
Using your first 2 initials and last name should work best in your case.
