Who gets host per game is determined by a live coin flip before the match starts. The options players get the choose from vary by league.
Madden
The coin toss winner is the host
The game is played at a Neutral stadium
College Football
The coin toss winner chooses to be the host or be home team
2K Regular Teams
The coin toss winner chooses to be the host or be the home team
2K Stage
The coin toss winner chooses to receive the ball first and shirts or skins
In rare circumstances, they choose ball or server first
FC25 FUT
The coin toss winner chooses who will be the host
Warzone
The coin toss winner picks who will be the host for Map 1
The host for Map 2 will be the other team
The host for Map 3 is determined by the most kills in Map 1 + 2 combined
Call of Duty S&D
The coin toss winner picks who will host