I think it is possible, you need to work with ui_control node, and develop you basic logic, for each user/password, for example:
if ( user/password == "user1/password1") then
show "x" group
hide "y" group
if ( user/password == "user2/password2") then
show "y" group
hide "x" group
For basic flow example that you could use to work with user/pass: Node-RED-Dashboard : Log-In, Session Management
For example to use ui_control node: Using the Control UI Node With Flow Example
I hope it can helps you!!
