Super+1 to 9 work for the first nine, but I thought why not have Super+0 for the tenth? I actually happen to have pinned exactly ten apps on Task Manager, so this would be quite handy - it’s always a pleasure to operate the system from the comfort of the keyboard 
I wonder what a way to do this would be…
In System Settings >> Shortcuts, go to Plasma Workspace and you can configure entries for the first 10 apps in the task manager as you wish. (If you have 10 pinned apps, then Task Manager entries 1 thru 10 will always be your pins.)
If you use Meta0, bear in mind that you’re unbinding it from its default function (it resets the zoom level, which is handy if you accidentally hit Meta+ or Meta- and start zooming).
Thanks - once you learn the names for these things, a lot easier than expected