This was originally for Skyrim LE, but due to some feedback from people who say the same fix can also help with SE, I have recreated this mod from scratch, as a form 44, legitimate SSE plugin (which now requires the SE version of SIC as a master. (below is my original description from the LE version (other than the tweaked requirements)

Hope this helps a few out there!
~dan

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If you experience constant CTD in the Soul Cairn, AND use Skyrim Immersive Creatures, this may fix the issue. I can only say it solved it for me, so figured I'd upload in case anyone needs it.

I was experiencing CTD in the Soul Cairn to the extent that I could not go more than 10-15 seconds before crashing. Long story short it seemed to be related to SIC in my particular setup. This could be in combination with something else so I do not intend to bash SIC in any way, it is an amazing mod overall and I continue to use it to this day. But anyway, it seemed that when SIC was not present, I did not get the CTDs, but with it I did. Now, there is an option in the SIC MCM to disable Soul Cairn spawns, which I did, but the problem still persisted, so I went into TES5Edit and basically disabled any SIC Soul Cairn spawns I could find in there, on a test plugin I created... and VOILA... no more CTD in Soul Cairn! So just in case this may help anyone else I figured I should share...

NOTE- I expect this will only work if you add this plugin while OUTSIDE OF THE SOUL CAIRN, or preferably before ever entering that cell in the first place, which was the way I successfully tested on my own game.

God bless,
~tcbflash 

REQUIREMENTS...
Skyrim.esm
Skyrim Immersive Creatures Special Edition.esp

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