In order to add a filter, you must setup an entity(could be non persistant) with for example a date attribute as filter.
Put the entity in a dataview(maybe use a datasource mf) and put the charts in the dataview.
Then on change of setting the datafilter create a microflow that refresh your dataview entity.
For the charts create datasource microflows that use your dataview entity as a parameter and handle the filtering with your attribute.
This way you will get filtered data in your charts.
I just saw your comment and I have got nearly the same problem.
I have got a “Time series” widget, which is showing some data from my mindsphere assets.
I get this data using a REST Call in a microflow.
Now I add the function, that I can pick the time range which data should be displayed.
I tried like you explained above, but honestly I don’t know exactly what to do. Can you please help?