[Fuchs2468]

But only in these two skins. I still have the third Arctic Horizon 2 and everything is good here. They do not interfere with each other.

Since all the skins mentioned use "script.skinshortcuts", this behaviour is normal. 
If you do not want this behaviour, deactivate it in the settings of "script.skinshortcuts", then each skin uses its own setting.
Deactivate "Share menu between compatible skins". 
After that, of course, you have to set your menus for each skin again with "script.skinshortcuts".
"Arctic Horizon 2" is an exception because it is already defined in the skin that it has its own setting.
I hope it helps you?