What should be considered when building a natural stone wall made of slate?

Dear forum members

I would like to build a few freestanding natural stone walls made of slate in my garden as a property boundary. It should look like a ruin and therefore should not have a smooth top but go up and down from time to time... somewhere between 1m and 1.8m.
I can’t find any posts in German-speaking areas that specifically relate to slate and what to watch out for when working with it.
What you do find, of course, are posts about natural stone walls.
They cover basic things such as:

[*]Foundation down to the frost line
[*]At least as wide as the wall will be later
[*]Rebar in the foundation, ideally extended so that it reaches the top of the wall to create a unit
[*]Wash stones before processing
[*]Use so-called through-stones to provide tensile relief within the wall
[*]Always build double-layered walls if freestanding

Do you have any further input for me? What is written above makes sense, but I find nothing that specifically applies to slate or whether there are any other pitfalls to watch out for.
Is there a special cement I should use?

I would appreciate any tips. I don’t want the wall(s) to be damaged in 5 years.
Thank you all and best regards
Marko

Whatever a Durchstein is supposed to be, by "zweireihig" you probably mean the stretcher courses? Do you want to do wet masonry?

I translated the "Durchstein" from English. They are called throughstones there. These are stones that are visible from both the front and the back. They are supposed to provide stability so that the two rows hold together as much as possible.

By two-rowed I mean, when you look from above, there are two rows next to each other so that you have a nice front on both sides. I will try to illustrate this with a picture.

Yes, I want to do wet masonry because I see a bit more stability in it for such a high freestanding wall.

I translated "Durchstein" from English. They are called throughstones there. These are stones that are visible from both the front and the back. They are supposed to provide stability so that the two rows hold together as much as possible.

So a classic wall with alternating courses of stretchers and headers (the latter would be your "throughstones").
Maybe the search term "Weinbergmauer" will help you further (?)
Your project is, to put it kindly, "non-trivial." Wet construction might be more achievable for a non-professional; dry would be better because of the structure's resistance to temperature fluctuations. I'd say everyone chooses their own test.

Nontrivial is correct. I have spent the last few days transporting 15 tons of slate stones into my garden with a wheelbarrow and neatly stacking them. But that is "only" the physically demanding part. I can handle that easily. Two questions interest me particularly: Which cement should I use so that the wall does not crumble apart again next winter? Maybe there is something that works especially well with the slate. Can I build the wall piece by piece or centimeter by centimeter with a day’s break in between each, or do I have to do it all at once because I always have to work "wet-on-wet"?

How are your slate stones shaped?