Pass login credentials from One Webflow project to another?

We’ve created two separate webflow projects that need to be separate so changes to one do not affect the other. However, I want both to share the same site password.

I set up hosting for each project, then I created a sub domain to point to the second project. We have the same password set on both. The problem is that now the user needs to type in the password twice as they navigate from one site to the other. If the user is coming from xyz.com, already entering the password, then click the link within xyz.com that directs to site2.xyz.com…I want that ulr click to got to site2.xyz.com, recognize the referral url is xyz.com, auto enter the pass field and auto submit.(and vice versa)

So I think I need to put a bit of javascript custom code in both sites to look for the referral url the enter the password if it’s friendly? Anyone do this before or have any other idea of how to accomplish this? Thanks, in advance, for your help.

Hello, please provide details.