Add All Products Page to Frontend Menus per Customer
Navigate to Customers > Customers in the main menu.
Click once on the customer to open it.
Click Edit Frontend Menu on the top right.
Click once on the menu to which you will add the All Products page.
Click Create Menu Item on the top right of the page.
In the Title field, type in the label for the menu item.
In the URI field, specify /catalog/allproducts.
Complete the other fields as required.
Click Save on the top right of the page.
The All Products page should now become available as part of the selected frontend menu for a specific customer.