Please be aware that Barnard is “need aware” for transfer students:
https://barnard.edu/admissions/transfer-applicants
Also, they limit the number of transferrable credits to 60:
https://barnard.edu/transfer-credit-evaluations
My daughter certainly had a great experience at Barnard, and I know that some Barnard women do join the university’s sororities.
However, the above two factors might complicate matters for you.