Oak is not naturally gray...not a great choice for longevity. When your home is custom sized that means you will continue to need custom finishes. You need to find a manufacturer you can order from.

Actually? You don't want to do gray wood anything.

If you want to trim out a wall? Fine. Not that way.

And please tell us which of the pics is actually yours

First and third look like her photos. Such a nice space. Do you want to do the wood only on the first photo end walls (it's split by a doorway) or just on the FP wall?

What depth are you trying to acheive? Do you plan to remove the bookcases?

IMO accent walls belong on walls with no openings. As for the wood you will need to go custom and honestly IMO your walls are already busy without adding another item

Would you consider a painted treatment for your accent wall?

Please don’t, wall with fireplace too busy for that.

I really don't think that treatment would be flattering in your space. Your room is lovely but is lacking some depth. At a minimum I would add some pillows with texture and color and replace the rug you have with something that has pattern and color.

Thanks for all of your comments. The decor and furniture are not mine. I will be moving into this home within the next few month and will be getting rid of everything in there. The bookshelf on the tv wall is going too (I’d like to cover with wall panels).

I would like to do the wall panels on both walls (opposite from each other).

I still think that the wood slats are not a flattering look for that space. You can do better than that.

Bookshelf looks great there, and giving you place to display decorative items and books. With pannels it will be nothing, just gray color….

When you install feature strips on a wall it's usually applied to a wall where there are minimal interruptions. Not a wall that has lots of built-ins or accessories on the wall. Note how this installation was able to use the short strips effectively on a much taller wall.

Your walls have too many distracting details for them to be effective as a wall treatment. Sorry but this is the best I can do to demonstrate how this would look on your wall. but IMO it doesn't suit this wall in its present state.

Thanks Beverly. I am going to take everything out of that space (paintings too). I am wondering what to do to the walls to add some texture to the room. The pictures don’t do it justice - when you walk in during the daytime, it’s very white and plain.

The wall doesn't need "texture"........ the room and decor need texture, AND some contrast, and some warmth.

You're getting rid of everything? Fine, Move in. Begin with great rugs, paint, furniture, decor. ......A.R.T.

Consider a grasscloth wallpaper in a light grey.

🤗

A good cabinet maker or carpenter-not a rough carpenter-will make the wood work even if seamed. Just fine a good one that deals in accent walls and good quality wood. You may even have to have it milled to suit your situation.

Wood lathe strips applied vertically on the wall

Fluted wall paneling

Wood Veneer comes in rolls and can be applied like wallpaper by an expert installer.

Wood Lathe strips are applied horizontally to walls.