You can start with basics. One is mid size with 7700 undergrads while the other is huge - nearly four times as large.
Size often matters - Chapman has a faculty/student ratio half the size, etc. and will be more residential.
Both will be strong in certain majors - so that’ll depend. Like Film at Chapman.
And I suspect you can get a good education at both but potentially more adjuncts at LB State. But also more areas of study.
Chapman says 1/3 are in Greek life. Not sure about LBSU.
As for diversity - Chapman is very diverse. But if it’s very diverse, then Long Beach is off the charts diverse!!! Super super diverse.
These schools are different enough. Why not visit both - talk to kids, profs, etc. including Greek life members - so you can make the best decision for yourself.
Will one stand out in life vs. the other? Likely not - but again, Chapman is known in certain areas - and LB State will have its strengths too.
These schools are so different you really need to visit and decide for yourself.
Good luck.