I was also getting this but with the error:
[Error: Module version mismatch. Expected 46, got 47.]
It seems there was a mismatch between one of:
The hexo in node_modules/.bin
The hexo in /usr/local/bin/hexo
The globally installed hexo which may well have been the one from 2.
My solution was:
npm uninstall -g hexo-cli
rm /usr/local/bin/hexo
rm -rf node_modules
npm install
npm install -g hexo-cli
refer: hexo#1742