This one looks the best option to me, but I haven't tried it myself. I might get one at some point to try it out.
The other 3 products that you linked won't work. The beethinking one is too thick (tall), and the larger Brushy mountain one doesn't line up properly on the Flow entrance (I have one, so I know from direct experience). The smaller Brushy Mountain one is designed to attach to an existing wood entrance reducer, so that won't work either - it won't be big enough.
If you have any ability with wood, I would suggest getting a 1x1" wood trim strip from a local hardware store. You can sand this to size to fit into the entrance, then cut a slot in it so that it looks like a standard entrance reducer. Jerry started one for me, and I shaped it to fit like this, using a sander and a jigsaw to widen the entrance:
I found that the wood needed to be 9mm deep at the inside of the hive, and 10.5 to 11mm deep at the outside. It took a few tries to get the fit snug - if you don't get it right, the bees can push it out!
It works very well. The entrance is too small for mice, but large enough for drones.
The alternative would be to buy the Bee Thinking model, and sand it down, but you will need to sand the long flat side only, so that you don't mess up the bee space of the entrance. Also, if the wood gets very thin along the entrance, the reducer may snap.