Is it possible and could probably be done using my existing scripts, but would likely require some work.
Adjusting brightness, hue, saturation and so on is done with one script. A second script then creates the various light effects. It does this by using "light annotation" files I made by hand, essentially using special reserved colors which are ignored by script one. This was a labor of love but took a while. One would likely need to do a similar annotation to create snow, fall leaves, etc. With the right colors it could probably be made to look like seasonal effects, but we'd have to probably discuss more before jumping into it, and I would want community help with the annotation work.
I may be able to think of some ways to automate part of this work; let me meditate a bit on that
Movement restrictions could probably be implemented via Lua script, but again here I defer to Flintlock.