OHSAA rules do not allow an EP. They have what is know as the DP/Flex rule. Here is a copy and paste from NFHS website on the "explanation" of the rule.
NFHS DP / Flex Player Rule
DP rule replaces DH rule.
There is no option to use the Designated Hitter (DH) instead of the Designated Player (DP) rule.
NFHS DP / Flex Player Rule
The DP / FLEX Rule will be used for all NFHS games at all levels. NO Exceptions ? The Designed Hitter (DH) is no longer an approved NFHS rule.
NFHS DP / Flex Player Rule
A DP does not have to be used.
If used it must be noted on the starting lineup.
A team using the DP starts the game with 10, but could end with 9 or 10.
BEGINNING THE GAME
The DP (POSITION) is the offensive player and must remain in same batting position for entire game.
The name of player for whom the DP is batting (FLEX) will be placed in 10th position in lineup
THE LINE-UP CARD
If replaced by a substitute (my insert, which can be the Flex player), the DP position remains in the lineup.
A starting DP may re-enter one time, as long as the DP returns to the original position in the batting order.