MAybe statign the obviu=ous but use a scheduled event for this on a repeat interval of 1 week, see https://docs.mendix.com/refguide/scheduled-events
Depending on how you want to export the data, create the export function in your microflow. Make sure the folder is accesible from your Mendix app and you'll probably need some java code for this as there is no user interaction in the scheduled event.
you can add schedule event by right your module and select add-->other-->Scheduled Event
So You can get like this.
We have option to give scheduler start date and time,interval and interval type.So u can choose your option based on your requirements.In microflow option u have to select your microflow which you want to trigger during scheduled time