I've been using the Camdo BlinkX with GoPros for a timelapse that has been going on for over a year. They also sell a waterproof enclosure for it. Not a cheap solution but it's been working great.
https://cam-do.com/products/blinkx-time-lapse-camera-controller-for-gopro-hero5-6-7-8-cameras
It's connected to a voltaic battery and solar panel. With a large memory card I only have to check it every other week. It's taking one image every minute, 8 hours a day, 5 days a week. You can schedule it to shoot video too.
Ted