Google has now released it's Find My Device network and app. I checked if there were any unknown devices in my house and found an Apple Air Tag which I think is my wife's :-)
But also you can buy now Android specific trackers and a few months ago I bought 4 of these
https://pebblebee.com/collections/all-products/products/tag-for-android
Sill have not been shipped to me yet as they were waiting for the Google device network to be made available . These work with either the Find My Device app on the Android feature, or their own app which an also tracks Air Tags. But the ones I bought are not compatible with Air Tags which is fine for me since I only got them to track my own stuff using my Android phone.
It looks like if you want a tag that can tracked with either an Iphone (using Apple Find My) or Pebblebee's own app you would buy these ones
https://pebblebee.com/collections/all-products/products/pebblebee-clip