BMO has been confirmed to be genderless.
BMO looks like a half-Macintosh half-Game Boy Color with Atari 2600 controllers. It also shares some traits with a Vectrex.
BMO is a medium-size green handheld gaming device, sometimes appearing with one or two controllers attached to it. When it's not being played it has an 8-bit face. The letters "BMO" are printed on its sides, indicating its name.
BMO's default controllers highly resemble the Atari 2600 game console controllers, as they both only have a joystick and one red button. BMO's controller sometimes slightly resembles a Sega Genesis controller for its button layout and handling design. An interesting note about this is that an Atari 2600 and Sega Genesis controller have the same controller input device in reality, meaning that both controllers can be hooked up to the same device without issue.
BMO is sometimes seen with two slots to plug in controllers and sometimes with a compartment on that spot that opens up to where controllers can be plugged in.