Hi @Anonymous,
There is no direct action to sync files from the SharePoint library to Google Drive.
But the is a workaround you can do it, please follow these steps to create your Flow to sync files:
Step 1: You need to create a folder named as your SharePoint library, mine is named LibraryA:
Step 2: We start to create a Flow with a manual trigger, it will run if you click the button, or you can create a currency trigger run every day.
Step 3: Get these files from your library, then Apply to each of them. Firstly, we need to judge each of the file whether is a folder, if it is a folder, skip it. If it is not a folder, get the file content and create its mirror file in the Google Drive.

Step 4: If the file has existed in the Google Drive, get the file id use the Get file metadata using path action, and then update it. One point that should be noticed is that we need to set the Configure run after of Get file metadata using path action as the previous action has failed. So, the file would be updated if the file has existed in the Google Drive.

Please have a try, I hope it can help you.
Best Regards,
Community Support Team _ Lin Tu
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