Ive got a Grippa reel and when i had a problem with the gearing, i took it to bits. Their electric motor was 12v . But its gear driven , no chain.
There are 12v motors out there, but they are expensive compared to those 24v scooter motors Waterworks used on their first electric reels.
As far as I'm aware Hannay electric reels use a 12v motor.
I'm not sure what Waterworks now uses on their latest variant electric reel. The spare part motor shown on their website has a 12v sticker on it, but that doesn't mean it's not 24v.