I'm sure there is a small amount of extra port work that would need to be done, the big one I can think of is text box size.
If the Switch version of those EDF games has a unique layout or size of its menus or text boxes compared to previous English localizations, then there would be some amount of new work involved in making sure all lines of text are sized appropriately, or edited if they do not fit correctly.
Past that, it's hard to see why they haven't put them out, I would love to play them again!
And to your other comment, I'm on a Kbin instance that has a funny time setting, you're right. I wish I could just say I'm a cool dude from the future.