FWIW, I don't use any animal subject detection modes even when shooting mirrorless but use a focusing mode like a mid sized Dynamic AF Area or the Large or Small AF Area mode (or Group in a DSLR) and position that in the viewfinder so it's a bit up and away from the feeder or flower so the AF doesn't latch onto the feeder/flower. After each sequence I'll refocus on the feeder/flower to get the focus close but position the camera so the feeder/flower is along the edge or in the corner of the frame and wait for a hummer to come in, feed and then back out before trying for a shot as shooting as they approach tends to scare them away(especially with DSLR shutter noise) but if they feed first they seem a bit more tolerant.
With a flower I'll sometimes take the image while the bird is feeding but usually wait until the bird feeds a bit and then backs up and away. They don't always hover there but they do that often enough that I can usually focus and capture a few images.
I've tried simple blinds that break up the human form like hanging a sheet between two stands and just standing behind it and have sometimes set up feeders just outside an open window and used the house as a blind. But most of the time I just stay quietly near the flowers or feeder I'm working and in time the birds come in as long as I don't make a lot of sudden movements but something as simple as letting the camera hang down and then raising it to my eye as a hummer flies in is enough to scare it away. So if the birds are particularly active I might hold the camera up in shooting position and wait, if they're less active and taking longer between feedings I'll use a tripod to stay ready but the latter assumes I'm working a specific group of flowers or a feeder and not moving around as the birds feed around a wider area.
Placing a feeder near some flowers and letting the hummers get used to coming into that feeder and then removing the feeder and placing a few drops of sugar water on the flowers is one way to get them coming and feeding off specific flowers but often I just see which flowers they seem to be visiting frequently and set up near those flowers.