Hi @MRipley,
As far as I know there currently is not away around the required 2FA. Your users would have to have a phone.
I’ve been informed by HubSpot technical consultants that 2FA will not be required when single sign-on is in place: “The 2FA setting in HubSpot only applies to the HubSpot-native login.” That might be a way out but requires an Enterprise license.
Best regards!