Facebook Photo to Google Photo
First, log into your Facebook account (mobile/desktop). Go to Setting – Your Facebook Information and look for Transfer a Copy of Your Photos or Videos as shown below.
Under Choose Destination – Select Google Photos
Here, you can choose Photos or Videos
Next, Sign in your Google Photo account and allowing Facebook to add to your Google Photos library.
Last, Confirm Transfer.
Done, the transfer is in progress.
You can check your Google Photo after awhile.
Cheers