@ArtK,

All of our products, brands, and services use your TP-Link ID to login, as this allows your devices to be registered to the same account, and eases the process for our teams when troubleshooting or a warranty claim is made.

You can add additional lastpass entries so that it should autofill for whichever app or platform you are using.

If your Lastpass is bothering you about the repeat passwords, I believe that they do have a function to either turn off the scanning for specific accounts or to associate a login with multiple sites.