In fact you put two questions, I answered the first … and the question in the title 
Guess you really want your second question to be answered, that is how to access the variables via Wasm…
Just install Visual Studio 2019 and have a look at the SDK-examples I would say… maybe below little tutorial would give you a kick start with Wasm gauges ?
… anyway I’d really advise you to change your title AND the question text. This topic will attract Python savants, it is very unclear that you are actually looking for Wasm solutions… specific types of variables… maybe you could tell more about what you’re trying to do ?