Figured it out, You have to press Shift and then a mini menu pops up that you can press 2 or 4 on to quick switch.
Gears 5 conditions you not to press Shift key for anything so didn't think of pressing it.
If you'd like to, you can remap it globally at the system level under Preferences -> Keyboard -> Accessibility. This answer has suggestions ranging from setting Cmd + Q as the shortcut for "invert colors" to "do not disturb".
Of course, this will change it for all apps though, and you'll still have Cmd + Option + Q for Force Quit, but that's obviously ...
Mac likes to be annoying when it comes to game shortcuts, but you can override the Command-Q shortcut to use Minecraft's method of dropping items by using Ctrl-Command-Q. If you want to learn more about Minecraft shortcuts you can check out this website.