As said already.
But with prefader sends being after insert FX 1-6 and post fader sends being after insert FX 1-8
You can multi buss inputs, you can not Multibuss outputs. One input can be assigned to as many tracks as you like…
Nuendo Direct routing allows multiple output routings. But since the ouput routing in Nuendo is also post fader / and post inserts, ánd you want it pre-inserts, that wouldn´t do what you want either…