Having a command line option to dump all the presets and plugins (with versions) being used by babel would be useful.

This would help to avoid the bug report back and forth: "provide your .babelrc or what plugins/presets you are using", and would be less error prone. Also would be a good way to verify your own babel set up.

The format of the settings dump would be canonical and unambiguous whether .babelrc or command line flags are used. Perhaps some basic sanity checking could be done for the presets and plugins specified as well.