how to offload contacts through USB? I have an old Android phone with a broken USB port so that it doesn't charge properly.  There are multiple Google accounts so that different contacts are associated with different accounts.  Possibly, some contacts have no association.

Can I hook up the phone as a USB mass storage device and off load all the contacts?  Based on similar questions, I'm primarily concerned with "Device Contacts" which were never associated with an account.

Having contacts spread across multiple accounts is a secondary concern.

I synced the accounts and will look into uploading the account contacts to Google contacts.  Still unsure how to deal with device contacts.
I recommend one of these two free Android apps, both of which I find easy to use:


Red Rock Backup Contacts, which exports to Google CSV, Outlook
CSV, or a custom CSV, and has no builtin restore (You can easily
restore using Google Contacts).
OBSS MCBackup exports to vCard
(one file per contact) and does have builtin restore.


Both of these apps export files that can be imported into most contact managers (not just Android ones). Also, both of these can email them to you if you are having trouble with your USB connection.

Note that files created by these apps, like all Android files, are subject to a bug where you may need to restart android before they are visible over MTP to transfer to your computer.