On iOS, don't think can do this.
On MacOS, can create a Smart List to catch this ("card is not a member of any group"). HOWEVER, that has not worked for me in quite a while (added it back just now, for giggles to see if the bug has been fixed).
Cross-platform, can have a Shortcut that finds and fixes the problem Contacts. Works for me, but I only have iCloud Contacts, no Google/Outlook/other, so not having to distinguish which account the contact comes from.