Out of batter's box

[CCassistcoach]

It looks like different rule for different organizations, but wanted more information. Can't understand why this rule would be different between organizations. Here is question...

Batter/slapper's "wheel" foot steps in front of home plate (field has not been re-lined and lines non-existent) and slaps ball foul.
Is batter out?
What I have found...
USFA says batter out only if ball hit in fair territory. NSA unclear. USSSA says batter out fair or foul (but if lines are not evident, benefit of doubt should go to batter). ASA-can't find rule.

Thanks for responses.