We checked the Vivid integration for Outbank. 

Due to technical restrictions of Vivid there is no integration possible:
Vivid limits the refresh to only one device. So if we integrate Vivid in Outbank, you would be logged out of the Vivid Mobile Banking App with every account refresh in the Outbank App - and vise versa. This would just be complicated - which is not our goal.

Maybe Vivid changes its mind, if many customers submit the request there. It would be great, if you could open a feature request for a web interface or an open API (without PSD2), that Outbank could use for the integration.

You can use the following link, to contact the Vivid Support: https://vivid.money/de-de/support/

Thank you for your support!