Add potato wedges to Instant Pot.
In a small bowl whisk together oil, lemon juice, oregano, garlic, salt + pepper.Pour over potatoes and toss to coat.Add broth and give it all a quick stir. Lock on lid and turn pressure valve on lid to SEALING.Press PRESSURE COOK and adjust timer to 6 minutes. When timer is done, press CANCEL and do a quick release of pressure by carefully turning pressure valve on lid to VENTING.
Once all pressure is released open lid and using a slotted spoon transfer potato wedges to a serving bowl, leaving liquid in pot.
Press SAUTE mode, add butter and cook sauce for a couple of minutes, to reduce it and thicken it.
Press CANCEL, then spoon sauce over the potatoes.
Drizzle potatoes with a bit more olive oil and another dash salt and serve immediately.(if you wish you may also top the the potatoes with some crumbled feta and a few black olives)