Pollen (grass and birch) allergy - outside air quality

It’s possible with the Openweather app (not sure if it’s pollen specific)

Or, when you have an OpenWeathermap API key and location lat & lon:
http://api.openweathermap.org/data/2.5/air_pollution?lat=52&lon=4&APPID=[yourAPIkey]

Screenshot from 2023-06-27 18-52-27

Which you can use like Robert stated.
Xmpl: