Infinite Minigolf

You can create a private match and invite a friend in. Then have them quit out after the first hole. You'll go back to the lobby and can restart until you get the achievement for 5 in a row (which took 6 for me).

Due to the amount of reports that having the 2nd player quit the game doesn't actually count as a win, here is another easy way to do this.
The simple answer is, land a hole in one on the first hole then skip all other holes with both profiles. Read further for better explanation.

You will need 2 consoles and profiles, or you can boost it with a friend.

- From the game's home screen hit the xbox button
-Invite your friend
-Once they accept, you will see both avatars appear on the home screen
-Select Online Match, then Create Private Match
-choose options; 2 player, party only, Simon's Jokes - Casual
- then select start

The game will auto insert both players into a game of 10 holes. Now simply land a hole in one with your main profile, then with both profiles pause and hit the skip button for the rest of the holes. Once the game is over it'll count as a win to whoever has the highest score, just make sure you see the podium finish screen.
You can repeat this exact same process 5x to get all the "online win" achievements. This method will take you about 5-7 minutes tops per game.

Do this all fast enough and maybe the game won't crash on you.
(A common problem I experienced)

Confirmed/Posted April 2022