Can the video sequence editor be used to add several image sequences together, on top of each other?

Here's how I'd do it outside of Blender with imagemagick in a bash loop:

for f in render1/*png; do
    frame=$(basename $frame)
    convert -append render1/$frame render2/$frame ./stitched/$frame
done

Then import the frames from stitched into the sequencer.

Would take two frames like these:

And turn them into this:

Can the equivalent operation be done directly in the sequencer?

Can the video sequence editor be used to add several image sequences together, on top of each other?

Here's how I'd do it outside of Blender with Imagemagick in a bash loop:

for f in render1/*png; do
    frame=$(basename $frame)
    convert -append render1/$frame render2/$frame ./stitched/$frame
done

...then import the frames from stitched into the sequencer.

Would take two frames like these:

And turn them into this:

Can the equivalent operation be done directly in the VSE?