Is it possible to send the output of a stereo track in Wavelab 8.5 to more than one per of ST output?
Using send to bus?
If you mean send to other outputs of your multichannel interface, yes, but it's a little convoluted:
You can either:
1) Duplicate your track, switch the Montage from "Stereo" to "Multichannel, free config" (in the lower right), click the "1:2" to the left of each of the tracks, and route the tracks separately from there, Track 1 to 1 & 2 and Track 2 to 3 & 4.
2) Don't duplicate the track. Switch the Montage from "Stereo" to "Multichannel, DVD Audio", checkbox "Enable additional DVD Audio", on Channels pulldown set "4 channel - Lf, Rf, C, LFE". Then click to the left of the track where it says "Lf:Rf". Set Top Audio to "Lf" and "Center". Set Bottom Audio to "Rf" and "LFE". It's a strange setup, but it works, sending to 1 & 2 and 3 & 4.
This all assumes your interface in Options/VST Audio Connections is set from channel 1 to 8 from top to bottom. The montage track(s) will output to 1 & 2 and 3 & 4 of your interface.
Maybe someone else knows a better way.