So I went through the long and difficult process of importing LUTs "definietly" in Premiere. Thank you to all your contribution, it helped me a lot.
Here's the necessary information
Computer : MacBookPro M1 Pro
OS: Tahoe 26.1
Premiere Version : 25.6.2
The problem is : if you plan to put a LUT to a video, everything works fine. But I work so : I put LUTs on effect Layers to avoid editing each video and putting a LUT of each (maybe I should do so, but when I don't have time, I skip what I can) So i tried to apply a LUT from the ones I imported on an effect layer, but it just doesn't work, it takes the ones from the technical list and replaces them with the position of the original.
Here's where my LUTs are :

and the proof that my LUTs folder in the premiere app is empty:

Here's an example:
- I try to select a LUT to put on an effect layer

- Premiere selects the eighth of the list (the last one from the originally provided LUTs)

- I try to select a LUT to apply on a clip

- Premiere has selected the right LUT, no matter it's position in the list
I really don't understand why it would be different to apply a LUT on a clip rather than on a layer effect, and why would the LUT order in the folder would matter. Any help would be appreciated 🙂