It's not the Greek language, your custom skin just needs an update to work on LE 9.x.x (missing texture files):
Code
2020-03-21 15:00:48.704 T:140011197126848 NOTICE: load skin from: /storage/.kodi/addons/skin.aeonmq8 (version: 2.9.0)
2020-03-21 15:00:49.116 T:140011197126848 WARNING: Trying to add unsupported control type 1
2020-03-21 15:00:49.161 T:140011197126848 WARNING: Previous line repeats 3 times.
2020-03-21 15:00:49.161 T:140011197126848 ERROR: Control 9000 in window 10000 has been asked to focus, but it can't
2020-03-21 15:00:49.379 T:140010747717376 ERROR: DoWork - Direct texture file loading failed for resource://resource.images.recordlabels.white/
2020-03-21 15:00:49.383 T:140010756110080 ERROR: DoWork - Direct texture file loading failed for resource://resource.images.studios.white/
If you want maximum stability, use the default skin.