Essential as in pretty much everyone agrees are good and worth having, I know no mod is essential in the literal sense, and opinions will change whats essential to each individual.
Looking for a bit of a list/collection cause otherwise I’ll go down the rabbit hole and end up modding my game to much to be playable… Which I wish was a joke, but that happened last time I got my itch on for city building, lol.
I haven’t played it yet, but I’ve heard that these are two good mods to have
Roundabout builder: https://www.nexusmods.com/citiesskylines/mods/73?tab=files
Traffic Manager: President Edition: https://tmpe.me/
Move It, Precision Engineering, TMPE.
I’ve not played in a long time, but those are the three that EVERYONE used to run as a core setup.
There’s apparently one that fixes the rampant land value issue that will break your city
