Will old Apple Watch models work with AirPower?
Solution 1:
Yes!
AirPower works with the new series 3 Apple Watch, as well as the Apple Watch Series 2, the original Apple Watch, the Appel Watch Edition, Apple Watch Hermes, and the Apple Watch Nike+.
https://www.macworld.com/article/3224389/mobile-accessories/apple-airpower-features-specs-price-faq.html
Solution 2:
The answer is no unfortunately.
https://www.macrumors.com/2017/09/20/airpower-apple-watch-series-3/
https://www.apple.com/watch/compare/