The Seasons of Iverstead
Using the Seasons of Skyrim framework with Base Object swapper both created by powerofthree Zeknapain took it to the next level with Seasonal Aspen trees which gave the aspens all four seasons.
Add in Shrubs of snow by wankingSkeever and DynDOLOD 3 by Sheson (which now supports seasons framework) and the entire landscape of Skyrim now changes with the seasons including the distant LOD.
Simply amazing, and the only game I know that dynamically changes the models used based on time of year in game (although to be honest I pretty much only play Skyrim these days so there may be others.......but I doubt it).
Check out the awesome work of these talented people here:
Shrubs of Snow
https://www.nexusmods.com/skyrimspecialedition/mods/63463
Seasons of Skyrim
https://www.nexusmods.com/skyrimspecialedition/mods/62861
Base object Swapper
https://www.nexusmods.com/skyrimspecialedition/mods/60805
Seasonal Aspen Trees
https://www.nexusmods.com/skyrimspecialedition/mods/63641
DynDOLOD
https://www.nexusmods.com/skyrimspecialedition/mods/32382
Disclaimer:
I run about 450 mods and my data folder is over 120GB.
It took almost 2 hours to generate SSELODGen for seasonal terrain.
About 45 min to generate TexGen and nearly an hour to generate DynDOLOD (with seasons).
So If you want to do this set aside some time.
Be sure you have your landscape, trees and flora pretty well decided in your load order because changing these things later will require re-generating the files.
For me it was worth it. Most of these processes you can start, and go do something else for a while. They will be done when you return.