Mono/Stereo inserts/plugins don't work on tracks and only work on a bus or FX channel, this means you would have to add a bus channel if you wanted to use an insert that takes a mono input and outputs in stereo AND then wanted to use the sends.
Or you could set the input of the track as stereo to do this but that seems impractical and doesn't make sense to do on a mono track.
I want to add a mono to stereo delay on a guitar fx track for example.
If you agree, please UPVOTE this.