As you have not listed which 4 mods(and versions), I cannot tell you which mods are outdated or conflict with each other. One problem appears to be that at least one of the mods have added a value to a dictionary that already existed. This can also happen if the user messes with the backup folder between multiple times applying mods. Something like the central values here:
var list = {
'Character Creation & Stats' : {
basehealth = {descript = "Character's health before modifiers", min = 1.0, max = 1000.0},
basehealth = {descript = "Character's health before modifiers", min = 1.0, max = 1000.0},
},
}
The second problem is a duplicate variable. If I were to guess, two of the mods are the Bugfix mod V6b and Expanded Sex 1.3d, with the conflict being that you used ES 1.3d rather than ES 1.3e.
Since the game crashes on start, the safe fix is to delete the program folder and extract a new one. Alternatively, you can force a partial reset by manually copying the contents of the "backup" folder and paste it over the matching folders outside of the "backup" folder (the mods menu will wrongly state that the mods are still active, but that has no effect). From there you can check your mod versions or try to apply a subset of the mods to see if those work.