I've been using I2Localization for a few months, and I started getting this problem after upgrading to the latest version of unity.
Upon opening or hitting play in a blank unity project with just I2Localization installed from the asset store and using default settings with an internet connection the editor freezes for 10+ minutes. I noticed these freezes don't happen if there is no active internet connection.
It appears to be waiting for a connection to time out before it lets the project continue.
Attached are the profiler snapshots of this happening, with the spikes highlighted.
I2 Localization Version2.7.0 f1