It was easier than I thought: I even had not to create a RestrictionTemplate.
Open a context menu of Roles configuration objects group and choose All Access Restrictions menu item. Create a new restriction. On the left side (Objects) choose all Catalogs and Documents (without of Sequences). On the right side (Roles) choose a role of branch users. Click Next button. Choose a right Read and a field Branch. Now in the field Access Restriction write a restriction
WHERE Branch = &CurrentBranch
The CurrentBranch should be created and set in SessionParameters. Now the greatest thing: when you click OK this restriction will be copied to all previously chosen objects. Some objects which do not have a Branch field are easy to find and delete: they have in Margins column <Other Fields> value.
Now we have filters by branches and it took about 5 minutes when you know how to do it!
Thanks to everybody!