Meantime i found the solution to see all my Planner task in Outlook calendar. This article helped me: https://support.office.com/en-us/article/view-your-tasks-on-a-calendar-8647d2c9-9bc7-466a-b5b3-74b3596fade2?ui=en-US&rs=en-US&ad=US
In Planner I have 2 options:
1. On My task select add to Outlook - this way i see all my Planner task from all plans
2. On a specific plan select add to Outlook - i see all the task from that specific plan
So i have an extra Calendar in Outlook. I choose to see this too and use overlay calendars. If i opt for a week view (or vworkweek) I see Planner tasks in calendar along with Outlook apointments and i can see Outlook task list in the footer of the calendar for each day.
If anyone has a better solution I be glad to know it.
Nice day!