The Google Dialer is found to be compatible with a greater range of devices

Despite its plain name, Phone may offer more expansive facilities than the average dialer app. It has Google-powered features such as Assisted Dialing, Nearby Places and built-in Duo video calling. However, it typically only works with phones from the Android One Program, Pixel-brand devices and those Xiaomi phones sold in Europe (in which it replaces the MIUI dialer). Now, however, it is possible that its developer is allowing it access to additional phones.

XDA correspondents have found that downloading the latest Phone public beta resulted in its ability to function on certain non-Google-updated handsets. At present, it appears to be those of a more up-to-date OS version and with a certain shared Android library (com.google.android.dialer.support) that can run the app. 

Therefore, these devices include the OPPO Find X2 Pro; the LG V60 ThinQ and Asus ZenFone 6 (so long as it runs the newest version of ZenUI), but not the Samsung Galaxy S20 Ultra or more recent OnePlus flagships.

It is always nice to have a phone that gains the ability to use new apps or tools. Then again, these apparent additions to the list of Google Phone-compatible units remain unable to use the AI-powered Call Screen feature: this seems to still be exclusive to the Pixel line.