They should be fine outside with maybe some protection if temps go to freezing for extended periods in your zone. They can take short freezes.

I'm in Zone 8 and now and then, we get some freezing temperatures for a few days at a time. The Sarrs and VFTs handle them fine.

I think yours will be just fine to over-winter outside. Once you confirm that, it's open season on how many more you want now that you'll see the over-wintering care is quite easy for your area.

An update.... Since temps have gotten down into the single digits (with a brisk breeze), it's a good thing I didn't leave 'em outside. And the main greenhouse hasn't gotten below about 50, so the plants never would have entered dormancy there. The VFTs and Sarrs were placed under a bench in the NW corner of the temporary (all fabric on tubular steel frame) greenhouse - the coldest/darkest place. That location has probably gotten down to just below 32F a couple of times.

But what does winter dormancy look like? Plants flattened and discolored...or ones that are just sulking and look like they ain't having any fun?

Cheers

The Flytraps will basically stop growing and have soil hugging traps. Some traps will blacken and die. Keep moist but not soggy.

Right, VFT leaves change with the seasons. The first time I thought they would kind of die off and be just a root ball waiting for spring, but I have since learned, that they're still having leaves, just low-lying leaves like tommyr said.

The Sarrs should also continue to have their pitchers upright. Some may turn brown from age, or maybe dryness, but otherwise, they still would have their coloring also, from my experience of the ones that I have.

So Sarrs and VFTs definitely don't change much during the dormant season as far as not being green or looking like they're not still growing, but they are resting.