Answer:
In RFEM 6 and RSTAB 8, you can freely set all keyboard shortcuts.
To do this, open the "Customize" dialog box using the menu "Options > Customize Menus and Toolbars".
Click "View" in the "Categories" list on the left, then double-click "AI Assistant Mia on/off" in the "Commands" list on the right.
Here you can define a new keyboard shortcut.