A lot of planes fly Belarus - Egypt, which means flying through Greek/Cyprus airspace.
Will be interesting if Ukraine and/or Turkey responds, as flights from Belarus to Istanbul would be effected too. Ukraine (and Turkey) are part of Eurocontrol, but not part of the EU.
Obviously Belarus will still be flying east to Russia
https://en.belavia.by/webroot/delivery/files/TimeTable_en_s2...
They appear to have 30 planes split between Boeing and Embraer:
https://en.belavia.by/company/air_fleet/