Press the Saute button on the Instant Pot and adjust to High heat.
In a large bag or container with lid, toss stew meat with flour, salt, pepper, and garlic powder. Shake until each piece is thoroughly covered.
Add the oil to the Instant Pot and wait until the oil is hot and shiny. When the Instant Pot reads "Hot," add the floured beef pieces in a single layer, careful not to overcrowd. Sear 5 minutes on one side, then flip and sear another 5 minutes or until very browned. Remove the meat to a separate bowl.
To the hot pot, immediately add the onion, soy sauce, worchestire sauce, red wine vinegar, tomato paste, salt, garlic, and Italian seasoning. Scrape all the browned bits off the bottom of the pot and stir constantly to avoid burning the tomato paste. Saute the onions until soft, about 7 minutes.
Pour in the beef broth and scrape any remaining browned bits off the bottom of the pot. Add the potatoes, carrots, and reserved meat and any juices to the pot and stir completely.
Turn off saute mode. Put the lid on the Instant Pot, turn the knob to sealing, and pressure cook on high pressure for 30 minutes. Allow a 20 minute natural pressure release.
Open the lid and stir. Add salt to taste and serve.