[JudgePenitent]

If you want to give this data away for free, thats noble of you, but might trigger lawsuits.

In general, larger players have connections to private apis that come right from the field. Sports betting, espn, etc all pay for expensive connections to get live data.

The historical data will be time consuming but most likely legally safe.

Its the live match results data that you should not scrape in my opinion. Technically it will take some time to set up, but its possible. Its the legal part of all this that I would not recommend.

If i were you, id make two services: free historical data, and a paid live data api. I dont know much about sports data api in particular, but my question is why isnt this already out there? Probably because its very expensive to get enough feeds to have a live api anyone wants to use.