A big hindrance for most mods (beyond simply needing to port the data with whatever was updated from Oldrim -> SE) is SKSE (skyrim script extender), which hasn't yet been ported over. Anything requiring scripts probably requires SKSE at this point, so it won't function with the new hotness. A large majority of the old 'texture' mods work fine as-is (with a few caveats) but many have already been ported. You can pretty much get '4k textures on everything' installed today.
Another thing to keep in mind is you may not see every. single. mod. that you had installed get ported. If it was a one-off 'check out this house on the lake i made!' mod from 2012, that might just not end up in SE.
I feel like I remember reading something about BSAs, but having said that, I have a BSA-enabled mod right now which works fine, so obviously it's not a blanket 'issue' right now.
OK, cool. If I remember this thread and remember to check it out some time later, I'll try to find that and link it here--I think it was on the main Nexus page for original Skyrim, detailing the upcoming SE page for mods (obviously an old post), or maybe it was within one of the mod pages or front page post of the SE main page.
The particular house that I want to restore was a pretty popular one, I think, and that dude has several mods and houses and I think some have been ported, so I could just wait. I think it is called "Riverfront" or something, and like many of those it was built along the river on the way to Whiterun. It's a sweet pad, of course, but the primary issue is that
all of my junk is stored there.
Of course, I could just try to start a new game, but I've already gone through 1 full (probably 96% pre-expansion) playthrough and two others at ~70% + each. I never finished the vampire or the Dragonborn packs, though (haven't even loaded the game since purchasing Dragonborn some year ago on sale). So, I do want to finish and try those out, but seriously doubt I want to go through an entirely new playthrough to get there. All of the crafting, looting and, of course, re-acquiring my precious antique can collection!
Thinking to what I last saw on steam--I've already got some 500+ hours in Skyrim? D: