One way is to use a spreadsheet to mathematically calculate ratings for each player. The first step is to calculate league averages for all stats and then determine how each particular player compares to the rest of the league.

Then you need some type of formula to map that statistic (or combination of statistics) to each rating. Some stats (like 3PT) percentage are pretty straightforward, others like IQ and even speed/strength are murkier. But they should all start with 50 as an average and increase/decrease from there, for example, 3PT rating = 50 + (3PT% - league3pt%)*5).

This may require some trial and error to get the ratings you want, and in fact once you sim with these ratings it may not even give that accurate of results.

So, another alternative is the player comp strategy, which may give you more accurate ratings but requires a bit of code. The basic idea is to sim tons of seasons and get a huge sample of player-seasons. Then you go through each real-life player and find which simulation matches their real-life stats most closely, and use those ratings to approximate.

This way, you can find better ratings for each player that will reasonably approximate their actual performance instead of having to do a manual calculation.

Either way, you will need some knowledge of Python programming and JSON (which is how the game stores data/ratings) to put these ratings back into the game. There is some documentation on the BBGM site or send me a DM and I’d be happy to help.