Super Mario Party will offer online play.
Revealed during Nintendo Treehouse Live at E3, the mode is called Online Mario-thon and features five different ever-changing mini-games. You can play against friends or people all over the world.
On top of that, Super Mario Party will have online leaderboards as well as some rewards, though Nintendo wouldn’t go into specifics regarding the latter. More information should be on the way soon.
It’s important to note that Super Mario Party will most likely be part of the paid service Nintendo Switch Online.