There is a utility player on our local Milb AA team that taught himself to switch-hit after he was drafted. He plays all positions, except pitcher, and switch hits.
Keewartson started hitting left just playing around. We had a hit-a-way attached to the basketball pole in the back yard and if nothing else, I believed at the time that it was building up the opposite side muscles. His 13U coach said if he was going to switch hit, that was ok, but he had to keep doing it, not going back to right hitting only.
While at a hitting lesson with his travel team, his coach saw him hit left, and encouraged him to keep doing it.
I am pretty sure that the college coach that son committed to saw him hit a HR from the left side at the WWBA 16U event.
Keep having hit both ways.