Neurosity Crown consists of an ADS1299 EEG chip & Wifi shield & single board computer on the hardware site:

A PiEEG hat & MNE Python:

You want to make PiEEG a hot seller – attach MNE Python to it & put it on a GITHUB page

has the same specifications on the hardware site.

The Neurosity Crown is 1 000 USD, PiEEG is only 350 USD & a Raspberry Pi.