Can someone who is self taught, teach someone else to play?

Can someone who is self taught teach someone else to play?

Yes...but.
There is a big difference between teaching and playing.  The trick to teaching is trying to remember the steps of the "learning ladder" that you went through when you were learning.  If you simply show the student what you are playing, you may create a "pedagogical leap"
(skip a step) and thereby create frustration.  Try to invent some exercises that are derived from the skill sets used to play the music you are trying to teach.  Convince the student that for them to succeed they need to make a commitment to success.  Best Wishes.
Steve Eckels  www.guitarmusicman.com