No you can not enable multiple mods at the same time, you can copy all mod files of every mod into one of your mod folders and as long as one mod don't overwrite files from another mod there would be no issue enabling it. This is one of the things i've complained about within the modding enviroment of sins, cuz as of right now a mod requires all gameinfo and texture files whether you modified them or not. however it does not require all mesh files, someone mentioned in the modding package thread that the requiring all texture files that were not modified was a bug, but not sure if this was confirmed or not.
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