Amazon.com: Haylou LS05 Smart Watch with 30 Day Battery Life, Biometric Sensors for Heart Rate Monitor, Sleep & Fitness Tracking, IPX68 Water Resistant, Metal Body w/ Touch Display, Bluetooth 5.0 : Electronics
Fossil Gen 5 Smartwatch review: No longer the best, but still a solid option
Here are Fossil's smart battery modes for Wear OS - 9to5Google