Thank you Zerofrost for creating this amazing armor! I hope you will come back to mod making again one day and you make an official HDT version of this beautiful armor! Also thanks to team TAL for making the physics and the model for Ornstein's armor. Cheers!

[Before you read the stuff bellow: Yes i assume there must be a simplier way to make this work but this is how i done it with very minimal mod making experiences and knowledge, but i managed to get it working so i provide you a detailed description on how i made it and a guide on how you can get it to work]

Hello! Everything you need to know is written bellow. [How i made it & How you can use it etc.]

How i "made" the plume:
I decided to "make" or "get" a plume somehow for the Dragonlord Armor by Zerofrost for personal use, and since im not really an experienced mod maker i did it the only way i could. I used a program Bodyslide and i took the mesh of ornstein's helmet from the DS item pack and i deleted the helmet's model but kept the plume and repositioned it, rescaled it, made it a misc instead of a helmet (in SSEEdit and Nifskope) so i can use it a top of the dragonlord helmet. I opened the original plume helmet's mesh and from the original non hdt plume i made a little "holder" for this plume so its not floating in the air and not too close to the helmet either so im not breaking the vibe of the armor. I really like it this way. I originally did this to myself so sorry if its a little too complicated, i didnt managed to make a hdt for the original plume so i used this method instead. But hey, its working and all the requirements and links are bellow if you wanna use it yourself!

TLDR: Its a plume from another mod that got a rescale and a reposition so you need that other mod aswell to be able to use this.

The Clipping "Fix" of the Robe:
So as you probably already know there is two versions of the chest piece of this armor, the regular and the "Robe" one, i like the robe one more because it just looks absolutely fantastic and it gives a different feel to the armor, but it has a lot of clipping issues so i fixed it with Bodyslide, rescaling some parts of the armor.
Also there is the old version of this fix without the red robe under the armored one, download that if you like it that way.

TLDR: Rescaled, repositioned some parts of the armor so it does not clipping anymore.

Now lets get to the point, you need to install these mods in this exact same order:
1. Dragonlord Armor from Zerofrost: https://www.nexusmods.com/skyrimspeci...
2. Dragonlord Armor Hotfix from Zerofrost: (same link as above)
https://www.nexusmods.com/skyrimspeci...
3. Dark Souls Armor Pack for SSE
[just search on google and you will find a reddit post, with the download link in the comments]
3.Dragonlord Armor HDT Plume & Fixed Robe
[my mod link]

Ok now you installed the mods in the correct order that i listed above, but you are not done yet since you cant equip the plume on top of the regular helmet, so to be able to do it you have to download and use SSEEdit and Nifskope and follow a guide called "Changing Body Slots - Skyrim notes to myself" (search on google, you will find the site), so open the Dark Souls item Pack by Team TAL.esp in SSEEdit when you get to that point in the guide i mentioned above, and change the body slot of "Dragonslayer Ornstein Helm" to 48 in both places the guide tells you (and obviously uncheck the slot that is checked by default, which stands for the helmet slot). So now that you done this you can start the game :).

After you started the game, get the armor if you dont have it already (You can find it in Silent Moons Camp, which is located northwest to Whiterun), equip the Plume helmet [Yes the plume one because we need the mesh of that one] and the Robe armor, now open the console [ ' ] and type "help ornstein", now you will see the ID of ornstein's armor. Now type "player.additem [ID of the helmet] 1" and equip it. And boom you have the working HDT Plume and the Robe Armor without any clipping issues :).