I have two sons and both are interested in riding alongside daddy in Zwift and I was wondering about people’s experiences here in the hardware setup needed. My oldest rides an MTB with 24" wheels and 8-speed derailleur, am wondering whether a zwift hub one would work with that or do I need some wheel contact trainer. My youngest has cerebral palsy and not enough balance reflex to ride a bike but can ride his Hase trike ok. I think indoors on a trainer the balance issue will be fine to use a two wheeled bike, probably around a 16" wheel size.
Ideally one trainer would work for both bikes, or some magical device that fits both. Fwiw I already have a Zwift Hub which I’m very happy with.
The Zwift Hub One trainer is compatible with 24" wheel bikes. This is documented in the “Tech Specs” section for the Hub One in the Zwift shop.
I’m not aware of any trainers designed to work with 16" wheel bikes but perhaps such a thing exists. I’ve seen modifications people made to wheel-on trainers to support tiny wheels, so the roller is extended enough to reach the wheel. I think there were some examples posted on the Zwift Riders group on Facebook in the last year. You could try asking over there to reach a broader audience.
Here’s an older Zwift Insider article on this method. May be a good starting point. A few people in the comments mention specific wheel on trainers and wheel sizes.