At Sleeper, we focus on head-to-head matchups because they create a more interactive fantasy experience.
We only offer that H2H style, but there are ways to run best ball leagues or ones with rotisserie scoring.
How to do Best Ball on Sleeper
You can create a league and have your draft as normal. Make sure to set the playoffs to "Off". As soon as the drafting is completed, the commissioner can lock all free agent and waiver moves.
Then, after each NFL week, the commish can use the tools on the web app to manually adjust each team's lineup, putting in the players with the highest scores from that week.
Once that is complete, the commish can use the recalculate button and have those changes applied.
There will still be matchups and records shown, but your league will use the Points For column to determine who the winner is. You can use that same column if you are focused on making it a rotisserie scoring league.