Season frozen salmon fillets with salt and pepper. Place a trivet inside a multi-functional pressure cooker (such as Instant Pot®) and pour in 1 cup of water, ensuring the water does not cover the trivet. Place fillets skin-side down on the trivet in a single layer.
Close and lock the lid. Select high pressure according to manufacturer's instructions; set timer for 4 minutes. Allow 10 to 15 minutes for pressure to build.
Release pressure carefully using the quick-release method according to manufacturer's instructions immediately after cooking time is over, about 5 minutes.
Meanwhile, mix together honey, mustard, and olive oil in a small bowl.
Set an oven rack about 6 inches from the heat source and preheat the oven's broiler to high. Line a baking sheet with parchment paper.
Unlock and remove the Instant Pot® lid. Carefully transfer cooked fillets onto the prepared baking sheet, skin-side down. Spread 1/2 of the honey-mustard glaze over each fillet.
Broil salmon fillets for 2 minutes. Serve immediately.