Paste your ESPN league link to see your league's full history: champions by season, all-time wins and points, playoff appearances, title counts and the best and worst seasons, going back as far as ESPN has your league.
ESPN league analyzer · ESPN weekly recap · ESPN power rankings
As far back as ESPN keeps your league, including seasons before 2018.
Private leagues work too. If you aren't the commissioner, League Lens gives you a one-tap message to send them asking to turn on 'Make League Viewable to Public' (League, Settings, Basic Settings). On a computer you can also connect your own ESPN login instead.