Denying access on a folder in all products

In all my products,

I have 2 folders - i) Tool  and ii) Design

And it the Product team

I have 2 user - i) Tool Engineer and ii) Design Engineer

I have to deny the Tool Engineer from either from viewing the Design Folder or if it can view it should not make any changes in it.

I created a custom domain and set the Deny permission on Full Control for Tool Engineer on Subfolder. And then associated this Domain with Design Folder. So now the Tool Engineer is not able to see the Design Folder.

But this is applicable in only one product.

I have multiple products and to apply this I ll have to do this changing of domain multiple times which I want to avoid.

Please suggest solution for it. Any other approach would be welcomed.