How to Make It
Gently stir together beef, eggs, garlic, onion, panko, Worcestershire, salt, and pepper in a medium bowl, being careful not to overmix. Form mixture into an 8- x 5 1/2-inch loaf. Place loaf in center of a large piece of heavy-duty aluminum foil. Fold up sides of foil to make a secure nest for meatloaf (you want the sides high enough so any moisture will not spill out).
Stir together ketchup, vinegar, and Dijon. Spread mixture evenly over meatloaf. Pour water into a programmable pressure multicooker (such as Instant Pot). Place cooker rack in cooker. Place meatloaf in foil on rack. Cover cooker with lid, and lock in place. Turn steam release handle to SEALING position. Select MANUAL/PRESSURE COOK setting. Select HIGH pressure for 25 minutes. (It will take 6 to 8 minutes for cooker to come up to pressure before cooking begins.)
Carefully turn steam release handle to VENTING position, and let steam fully escape (float valve will drop). (This will take about 2 to 3 minutes). Remove lid from cooker. Let meatloaf stand in cooker 5 minutes. Carefully remove meatloaf to a platter; discard foil and drippings. Re-spread ketchup topping over meatloaf, if needed. Cut meatloaf into slices, and serve.