Remote for pool light switch
I'd see no reason it can't be? Lutron Caseta light switches have remote controls if you have line of sight to the switch. They also come in a HomeKit version if you don't. So long as you get the amperage right - go for it. With the HomeKit versions, you could be outside by the pool, possibly out of wifi range and still turn it on over cellular data.

We have 3 of the HomeKit ones in the house and they work really well and are fairly easy to setup. It's nice to leave for work early in the morning when it's dark out; turn on the first floor lights as I'm getting dressed and not have to walk through a dark house, step on a cat, etc...