A more "Grid style" arrangement of the source and target segments is very well possible in Transit NXT, since the green source pane and the red target pane can be freely positioned inside the Transit NXT window. A "horizontal" layout is very well possible.
Thanks, I didn't realize that! Also learned other things via a comment left on YouTube by Tristamson.
BTW: It would be nice if Transit would allow export of projects to XLIFF.
I think you have mentioned a previous version of Transit supported export to XLIFF. Since the feature is no longer present in the current version, chances are its removal was a deliberate decision (whatever the reason behind that decision was). STAR appears to be a rather secretive company, so it's difficult to know what is going on.