The option for equipment meant for the hearing impaired is possible, too- always short range but the fidelity isn't particularly good, either.
If they can get approval for this (and other churches are doing it in the US, including the one my cousin attends), one way to avoid RF extending too far is placing the broadcast antenna in the center and setting it for the minimum power needed to reach the perimeter.
In the midst of a pandemic, churchgoers are driving to church--and staying in their cars
time.com