The phrase "different loadouts" means having various combinations of equipment or weapons. It refers to a person or group using different sets of tools or gear for specific purposes or situations. Full definition
As for the multiplayer, it offers up to 4 player co-op play across any of the story levels, which will allow for different loadouts for people wanting to screw around. (jgghgames.com)
While the game would prefer that players experiment with different loadouts and techniques, the small chainsaws are so convenient and effective that there's never a good reason to use anything else when dealing with bosses. (gamecritics.com)
While this can and sometimes does result in players sticking to the very first weapon they like to use, most of the time it offers up the freedom to try completely different loadouts. (wolfsgamingblog.com)