Rob, yes Magix Movie Studio and Magix VPX do (I can't speak for Vegas).. You can either turn the horizontal clips on their side or you can crop them down so that a portion of them will fit into a vertical/portrait phone screen. This is what that crop would look like:
Overall program view showing the 9:16 crop box (which can be moved anywhere and further shrunk or expanded):
Cropped view:
The Magix Movie Studio program has presets for 9:16 (shown above), Square and an Instagram preset of 4:5 (1080x1350) but you can easily create any shape/ratio video you like.
Movie Studio has that option create a new project, in movie setting choose Social Media and then choose vertical ( 1080x 1920) 9:16 instagram stories then if your original recorded video has a different size you have to crop the video to fit the part of the video that you want to show or use keyframe point to move the video to show other parts.