OT: I only need Outlook or at least a decent Groupware Client for EWS (EWS for Outlook Online Sync/the customer version)/office365. That does not have sync issu

OT: I only need Outlook or at least a decent Groupware Client for EWS (EWS for Outlook Online Sync/the customer version)/office365. That does not have sync issues, etc. Bonus: if it can sync Contacts with Linphone. And I would pay for it after a 10days testing period. electron version is ok, but not preferred.