I started Zwifting last year and was looking for a fan upgrade. A heart rate controlled fan is quite expensive, and making one yourself is way more fun after all.
I present: ZwiftWind, the ESPHome controlled fan based of an Audi 80 180W fan.
Plenty of hurricane force wind, that is following my heart rate:
Explanation, circuit and Yaml on Github:
https://github.com/jongdesteven/ZwiftWind