Cold Sweat is a great and immersive mod, but unfortunately it only supports Serene Seasons and is a bit coupled.

Not sure if it will be possible to add other seasons.

Adding support for mods wouldn't be as simple as a config, if that's what you're implying. Every mod has its own systems, and Cold Sweat needs to directly reference their code to know the current season and other info.

Cold Sweat has a very open and well-documented API, so adding support for mods with Java would be relatively simple as far as modding goes. The SereneSeasonsTempModifier class provides a good blueprint for this as well.

oh i see, thank you. The reason I had doubts was that I had seen a mod before that created a dedicated item for this, which led to my misunderstanding.

Did you add them to the player? TempModifiers aren't automatically applied by default. If you want your TempModifier to be added as soon as the player spawns, look into GatherDefaultTempModifiersEvent

This blueprint is a bit confusing to me, I'm not sure when the TempModifier was added.
Should I add the missing modifiers myself? Although I have completed the registration.
But getModifiers(Trait.WORLD) I will find that I can't get the modifiers I registered.

I had not found this code before, I did so by searching for code references to Serene Seasons, which led me to nowhere.

Now it should work, btw Cold Sweat handling whether it is raining in the area well so I don't have to add more Mixins.