Line a baking sheet with parchment.Stir ricotta and 2 tablespoonsoil in a medium bowl untilsmooth.
Mix in garlic and next5 ingredients.
Add pork; gentlyfold until just combined.
Scoop out scant tablespoonfulsof pork mixture. With dampenedhands, roll portions betweenyour palms into 1" balls; place onsheet. Wrap 1 sage leaf aroundeach ball; press gently to adhere.
Place flour, egg, and pankoin 3 separate medium bowls.Working with 1 meatball at a time,dredge in flour, rolling betweenyour hands to remove excessflour. Dip in egg; allow excess todrip back into bowl.
Roll meatballin panko, pressing gently to coat.Return to sheet.
Attach deep-fry thermometerto side of a large heavy pot.
Pourin oil to a depth of 2".
Heat overmedium heat until thermometerregisters 350°F. Line anotherbaking sheet with parchment; seta wire rack inside.
Working in batches, frymeatballs, turning often, untillight golden and crisp, about1 minute (they will finish cookingin the oven).
Transfer to wirerack; let cool. DO AHEAD:Meatballs can be fried 1 monthahead. Store airtight in freezer.
Preheat oven to 275°F.
Bakemeatballs in batches on wirerack in baking sheet until cookedthrough, about 15 minutes.
Serve,or keep warm in oven for up to45 minutes.
Pour some warm marinara,if using, into a small bowl.