This mod adds:
*Skooma recipes for existing Skooma (not Redwater, but don't worry about that)
*Several new varieties of Skooma, some with special effects. Also some new types of Skooma as well. 
*Skooma beverages and recipes to make them (not added to vendors, but can be sold to Inns!)
*Skooma Shack with skooma still/cooking area, skooma starter supply chest, skooma chest, woodchopping block, skooma cook's outfit, Skooma Cook's Journal, & shack has 2 entrance/exits and you can fast travel from inside. Once discovered you can fast travel to the shack.
*Basic story through notes and a book explaining the Skooma Shack and why it's now empty. First letter can be found in a little burned-out fire behind Ysolda's house and there's another copy inside her house under the iron a bit next to the fire. (Don't worry, the letter at Ysolda's will tell you the basic location of the shack. The following letter is on a table/under the table at the shack and just explains some plot, the Skooma Cook's Diary lists the recipes and completes the plot.)

There shouldn't be any conflicts, at least not that I found. 
I highly suggest using More Growable Plants SE with this mod. While it isn't needed for the mod to function it is needed to grow moonsugar, and it's only really worth it if you grow your own moonsugar for the skooma if you want to make a profit.

NOW with an ESP-FE version thanks to LordLucian7.

UPDATE: V1.2- Added scripts to the notes to help further keep them in place. (no worries about the scripts, the scripts are from the base game)
V1.1- I've added another "starter" note inside of Ysolda's next to her fire, and if this one decides to fall through where it's sitting or gets knocked into the fire you should still be able to "see" it and pick it up. In Ysolda's house is where to get the note if you use a mod like Open Cities where the fire & note won't spawn outside of Ysolda's house. If there are still any issues with the notes not spawning, see "NOTE" below.

NOTE: I'm getting news of issues with the starting note behind Ysolda's house. I have "fixed" this for the updates, but if for some reason it still disappears you can spawn it with console commands. The note file is "SKOOMANoteYsolda" all one word. It can also be easily accessed using the mod AddItemMenu (https://www.nexusmods.com/skyrimspecialedition/mods/17563).  The note is just for story purposes, and if you want to just skip the note, it sends you to Cliffside Retreat where you will find the Skooma Shack "next door" (map of location added in the pictures).

KNOWN ISSUES: 1. Mods that change Whiterun's exterior or change the cell info can cause issues with the burned-out fire and note behind Ysolda's house.
                              2. Placed notes in Skyrim are notorious for not staying where they're supposed to be, and I knew that but for some reason I did it anyway for
                                  the story aspect. Sorry about that, I just didn't think about it, but the actual mod should still be unaffected by this issue otherwise.