--ftp-pasv

Use passive mode for the data connection. Passive is the internal default behavior, but using this option can be used to override a previous --ftp-port option.

Reversing an enforced passive really is not doable but you must then instead enforce the correct --ftp-port again.

Passive mode means that curl tries the EPSV command first and then PASV, unless --disable-epsv is used.