This is a hypothetical question. Someone has Win8.1 Enterprise installed, which he reactivates every half year with KMSPico. He wants to add Windows 10 and have a dual boot system. But he doesn't have a product key. What can he do?
Install win 10 on another partition and dual boot it, it's as simple as that. KMS activation runs inside windows, so both installs can be separately activated by KMS (8.x/10) or HWID (10 install only).
Thank you! I should have realized that myself. I appreciate the fast response and easy solution to this hypothetical situation.