If you're trying out Nintendo Switch Sports online over the weekend, you better not share anything about your experience.
No that's not me trying to avoid spoilers, that's an official requirement by Nintendo when you agree to download the playtest.
On the My Nintendo page where you can pick up a code, this small bullet point is listed under important information: "Participants are forbidden from sharing information about the Online Play Test publicly, including the sharing of screenshots or video footage from the game on social media."
It isn't clear what exactly the consequences are if you do share anything, although Nintendo will likely issue takedown requests to any content shared on social media platforms or video hosting sites. Playtesters aren't signing a non-disclosure agreement, so you're very unlikely to get in any real trouble personally (though don't take this as legal advice, Nintendo has formidable lawyers and isn't afraid to use them).
The Nintendo Switch Sports Online Play Test will be available for five sessions in total, each one lasting 45 minutes. The test will be exclusive to Nintendo Switch online users and will not be compatible with Nintendo Switch Lite consoles.