Ultimate Branding in a multiple Domain Mapped Network

I am working with multiple domains mapped in my multisite. Is there a way to set a custom login page per domain?

Is activating the plugin on the individual sites an option?

Also – is there an updated doc that covers all the new modules? Specifically the Multisite Registration Module – and the Multisite Favicon Module.

I’m using a Genesis theme on one of my mapped subsites and it has the “site icon” setting in Customizer – should I upload the icon on both places?