I would imagine it will work. I know a fella that used a plastic yard flamingo painted to look like a heron as a confidence decoy. I hunted over it, and birds worked the spreads with the "heron" as well as without it. The measure of success being did it scare the [censored] out of birds or were they indifferent.
I think the hard plastic decoys being sold today are designed to catch the hunters eye more than that of the birds. We successfully hunted over solid grey and solid flat black foam decoys with lead weighted keels for many years. They had zero detail, certainly not like today's dekes. Some of the hard plastic decoys for sale at Cabelas are nice enough to use as a display on a fireplace mantle.
Do you ever get the feeling you're being watched? Because if you do, I'll stop doing it.