Multiplayer At Home: One game, two consoles (PC/XBOX)

Just thought I would share this with everyone who may be wondering how they can play at home with a friend, your kids, your partner, etc. The Back Story: I purchased SoT nearly two years ago when my work colleagues suggested I join them in playing online. Lives get busy/new games etc. Only recently have been on a kick of plowing through Tall-Tales. My girlfriend expressed that she'd be interested in helping me with Quests as I've been stating of how difficult a Quest can be as a single player. Seems standard enough, right? If she had a copy of SoT too, we could play together, however, she does not have a computer for gaming. What I do have though, is an Xbox S series that I can install SoT to (via the Microsoft purchase) and she can play on that; but you can't play on both Xbox AND the PC using the same account...Long story short: I purchased the standard Game Pass on my Xbox under the same account that I purchased SoT. I have to SIGN OUT of my account on Xbox, SIGN IN with her Microsoft Account (which was created for her daughter to play Minecraft) and boom, we're there. It didn't seem so straight forward at first...I had many thoughts during this process: Do I have to buy a second copy of the game for this to work? And, if Microsoft sees that the game is already purchased, do I have to buy it on a different account? Should I buy it on my OTHER ACCOUNT or HER ACCOUNT? But I couldn't purchase it using a different account as the M-Store is telling me it's already owned/installed. I'm also going to need a Game Pass for this game to work. Do I Need Core, Standard, or Ultimate?? I read online that you can add "FAMILY" to your "HOME" Xbox. So I did that. Apparently, you only need Game Pass on your Home Xbox for all profiles to enjoy the benefits. So, after much consideration over which subscription I may need, I took a shot and went with the standard Game Pass. I didn't care to pay the $20 as I didn't need all the features, I thought to try the Core cos it was the cheapest, but figured I might as well spend the extra $5 for a fuller catalogue of games. ($15 is like a single lunch order these days.) It wasn't working at first, but after some troubleshooting (log-ins, an update was done on my Console companion PC), we were both in a server! One game purchase, running on one PC, one Xbox S series with Game Pass on my main account and now, I've got my first mate at home to help me with my Tall-Tale Quests. I hope this helps anyone looking for these kinds of solutions for at-home play. I'm sure this knowledge exists elsewhere but I was having some trouble finding the right answers and wanted to share my experience for the benefit of others. Happy sailing/hunting!