Hi. A yo e has News about the first landing in Greece via a port of entry? The re is not any news about the possibility to fly direct to final destination from Shengen area?
Ioannina is best coming from the North, but check opening hours carefully (based around commercial flight) and they currently have no Avgas
https://www.aopa.gr/en/flying-in-greece
Check paragraph “2. How to ENTER – EXIT Greece and save costs”
I recommend you read the entire guide as it contains important information.
Greece signed Schengen but disregards it.
The only exception I know is Kithira LGKC which kind of operates it. EuroGA airport database report.