DISCLAIMER: The method below could eventually become patched, at least partially. There seemed to be some sort of protection when we tried this for the playoffs on next gen. In general this seems to work better on old gen but it is definitely possible to get the achievement on both versions using this method.
Posting this method might also lead to public div 1 clubs becoming harder to find. Generally speaking if you find yourself in a spot where you want to hijack a division 1 club timing is a factor. At the time of writing this guide a new season has just started so public division 1 clubs will be hard to come by but this should sort itself out in a couple of days.
Also please be aware that is not possible to go for this achievement during the playoffs. Each season consists of 6 weeks total, the last one is reserved for playoffs. You can use the calendar to check when the playoffs are happening.What you need is at least 4 players and 2 division 1 clubs located in the same matchmaking region, preferably one of them in the playoffs or at least close. The second club doesn't have to be in the playoffs, division 1 is enough. It doesn't matter if you own those clubs yourself or look for public clubs, just be aware that you can get screwed using the latter (look for clubs with a squad size of 1 - 10, then preferably choose one that only has 2 to 3 people in it with no one online). I also suggest you use a matchmaking region in Asia or Australia, one that is less active, though timezones are also a factor here. Maybe try to be a bit careful regarding the latency as well, if you're too far away the game might lag horribly which in itself is not a big deal cause you're not going to play the game but you might get kicked which could ruin your run especially if you're playing the last match. Only half of the players will be going for the achievement at a time but it's not a big deal as it's a fairly quick method. You will need a third division 1 club from the same region that again preferably is close to promotion already to get the achievement for the remaining players. If you own a division 1 club already you can also change the matchmaking region under club settings. It's possible to do this with more than 4 people but it might make it harder to find each other.
The players going for the achievement first should get in the club that is closer to promotion. Once you got the clubs ready and have distributed the players evenly you're ready to go.
1. In both clubs, one player should take the GK spot whereas the other should play Any.
2. In both clubs, make sure the lobby settings are as follows:
*** Spoiler - click to reveal ***Match Type: League Match
Kit: Doesn't Matter
'Any' Position: On
Match Keeper: On
Best Match My Team Size: Off (we've first tried using on and it worked, but if you have an uneven number of players it might prevent you from finding each other, we were still able to get this done just fine with it being turned off, maybe play around with it a little if you're having trouble)
If you're reading this guide you're probably planning to do this with other Xbox players only so the lobby's crossplay setting doesn't matter. As far as I can tell the setting depends on the setting of the first person to enter a lobby. Just pay attention to the setting if you're doing this with PS/PC players. You can see the crossplay setting in the top left corner of the screen.
3. Once the settings are correct, you can start searching. We deliberately waited about 5+ seconds to start searching with the second club as there seems to be some sort of protection that can prevent you from finding each other if you're searching at the exact same time. I highly recommend at least for the captain to be in a party together for this.
4. If you find each other get into the match, if you don't just dashboard on the Kit Selection (don't forget to tell each other the team names beforehand)
5. If you're in the match, the team that isn't going for the achievement should concede a goal and quit after 5 minutes (waiting until the 5 minute mark might not actually be required, if you can provide more info on this let me know and I'll update the guide)
6. Rinse and repeat until the last match. You need to win 4 out of 5 so keep quitting until you got 3 wins. If you can't find each other anymore switching captains and restarting the game can sometimes help (obviously we don't know if it actually made a difference each time). Hijacking another public division 1 club is also an option. I've used this method a couple of times on both gens to help people get the achievement and it seemed to work quit a bit better on Xbox One.
7. I don't like writing all caps but THE LAST MATCH HAS TO BE PLAYED OUT FULLY. If the match ends prematurely you won't get the achievement so make sure no one gets kicked for idling. Achievement should pop after confirming the match result.
The club that you just used is in Elite division now and can no longer be used to go for this achievement so if you want to get it for the others you'll need a third club as has previously been mentioned.
If you got anything to add let me know in the comments.