Do those even exist?
Curious to know if an external HDD could be plugged into one of the base units USB ports. As well as an ethernet port. Prefer wired to wireless when things are stationary.
My guess is that the answer to both of those would be no. One of the main selling points of the console is that you can pull it out of the dock at any time and seamlessly transition into a portable device. I prefer wired over wireless too and I already have external HDDs in my house that could be used but I doubt Nintendo is going to want to support things that limit portability.
Going with an external HDD would mean that not all of your games are playable in portable form. What happens if you pull the Switch out of the dock while you are playing a game that is installed on external storage? Also, it seems like the games are going to be quite a bit smaller than PS4, Xbox One, and PC games. Most AAA games on those platforms wouldn't even fit on the 32GB the switch comes with. Something like this 128GB card for $39.99 will probably work well enough for most people.
Amazon product ASIN B010Q57S62
I'm pretty sure the Wii and Wii U don't even have ethernet ports and those aren't designed to be portable. They sell an adapter that plugs into a USB port for people who want to use ethernet. I suppose they could make these compatible with the Switch too. I think this is probably more likely than supporting external HDDs.