@TangoE30
A quick update and I finally think I figured it out, at least for MMM-OpenWeatherForecast by:

Subscribing to Open Weather’s One Call by Call (https://openweathermap.org/price) Changing my node_helper.js line 44 from 2.5 to 3.0 :
var url = https://api.openweathermap.org/data/3.0/onecall?"

I hope this helps someone else because it was difficult for me to understand why some modules would work and others would not with the same API key.