At the moment my Tooltip looks like this:
Now my question is, if it is possible to make a ToolTipTemplate to show data from more than one Graph
Hi @kryptoLuc,
This isn't supported at the moment but is something we plan to implement at some point. Right now tooltips are per series.
Ok, thank you 
Do you have any idea when this feature will be implemented?
Hopefully some time after we release Radzen Blazor Studio. Feel free to open a feature request so you can track its progress.