I agree we need to swap out a few players in January, but not sure I agree with your list.
Although he had a bad 20 minutes yesterday, there have been two quite recent games where Agyei has been amongst our best players. Once when playing centre forward and the other when playing wide left. His worst position is the one where Robinson plays him most often, like yesterday.
I think we also need a bit of short termism to avoid relegation, so would keep Henry this season and hope his form returns.
Eastwood I agree needs to move on, and also in sending Shodipo back who has been appaling in his last few appearances.
I'd also try to get shot of Hall and Hanson, one of whom seems past it, and the other has never been decent and is always injured.
The other player I'd have no qualms in seeing go is Sykes, as unfortunately, I think he is weak on the ball and never has a game where he seems to make a decent impact. Nowhere near enough assists or goals.