New Caledonia → Guinea
New Caledonia plugs
Type C
Type EGuinea plugs
Type C
Type FShared plug type: C
Compatibility: Compatible
Voltage — New Caledonia 230V — Guinea 230V
Voltage is the same. Your devices should work normally.
Device compatibility (phones)
Phones almost always support 100–240V, so yours should work safely. Check your charger label to confirm.
You likely only need a plug adapter (if socket shapes differ). Voltage is close between these countries.