I assume the foreigner limit will not apply for them? Or will it be like "only two non-Belarus players" for them?
They will play without the foreign player limit, as it was announced the other day. Their participation in the 18/19 season is officially confirmed, as is the one of Lokomotiv Kaliningrad. The league will have 12 teams next season.
It's possible that some other foreign teams will join the league in the 19/20 season.