good morning graham .. no plans at the moment to implement, lesson learnt from when davis airlink was added the initial release was confusing and lots of trial and error .
first inspection or thought comes to mind i cant see how the weather34 API can support multiple air quality sensors already it is at the limit of what can be sent .the API was built around a weather station primarily Davis hardware, this producing a lot of data realtime and historical data .
for example you have yourself 3 air quality sensors each sensor would require 9 additional api strings to deliver realtime data and more for historical data i.e average,max,lo etc that is an additional from top of my head a guess of 38 extra api strings to be sent in the API there are currently 197 strings all required adding an extra 38 will take it beyond the limit which is has been reached .only way possible is to either remove some existing strings and compromise the actual weather station data output i.e lose some data features from the davis output or produce a new short API dedicated for air quality sensors .that said how many will actually own more than one outside or two with a indoor location..
end of the day end user is not interested in the issues that arise when trying to accommodate extra sensors from multiple brands
most will think if meteobridge supports its easy to implement but one thing meteobridge lacks is clear documentation of how all this extra mixing of brands and additional sensor capability is properly implemented and most importantly for any template developer,designer is what the expected string should be.its too often left to the developer to pull his hair

out at guessing what is expected especially in the case of the developer doesnt actually own any of hardware .
for now purple air, luftdaten will remain as it is once some clear documentation and clarity of how it and what strings are expected I will just wait .as Boris mentions its experimental so in my eyes its not ready for prime time template use best to wait to see how it pans out then move forward .
@Boris a document with meteobridge output string capabilities is long overdue especially with all the new mixing of brands ,a document would make life so much easier for developers of templates etc , adding new meteobridge features would be a lot easier.That said writing documents can be a tedious affair but long overdue.the current wiki template page doesnt cover all possibilities and new additions.