Help: Show news from subsite to main site (multisite)

Hello, I know SportsPress can be used just for one league (for example: football), but I want to create a website for multiple leagues (for example: football, basketball, voleyball and etc) and to do that I need to use MultiSite and subsite for every league.

Can you suggest me how to show news submited to subsites in the main site? I want to publish news about different leagues and to show then in the main site?

Thank you.