Turkey won't be sending any F-16s. Not when the US has banned them from buying F-35s.One thing apparently, US not gonna send their stocks of F-16's. Maybe Norway's F-16's or Netherlands or maybe Belgium.
Although ideally it should be US or maybe Turkey, as Turkey have factory level maintenance facility for them and enough numbers to not deplete their own air force.
It is highly likely European F-16s will get sent to Ukraine, since it will only increase demand for the F-35 as they fail to deter the Russian Air Force. Sending aircraft piecemeal with poorly trained crews will prove of little use however. Sending the F-16s in Western Europe to Ukraine will also irrevocably weaken European air power. If a significant amount is sent, it might weaken European air power for the next half decade or even worse.