Periorbital edema 26 days post-op. Is this normal?

This can be a problem but usually takes care of itself.  Occasionally, dilute steroid injections might be indicated for refractory cases but I tend to be conservative if the trend of the swelling is favorable.

Most likely, these areas represent malar mounts and will improve as swelling subsides. This may sometimes take up to 3 months.

periorbital edema can sometimes last for a long time but it will eventually resolve.  Fat transfer can cause a lot of persistent swelling especially if liquefied fat (not fat cells) have not been separated away.  This should resolve with time.