In a small bowl, combine 2 tbsp low-sodium soy sauce, 1 tbsp oyster sauce, 1 tsp white vinegar, 1 tbsp agave syrup, 1 tbsp grated ginger, 1 grated garlic clove and 1 tsp cornstarch. Whisk until the cornstarch is fully dissolved and the sauce is smooth.
If your shrimp are frozen, thaw and pat them dry. Slice 1 green onion and set aside.
Heat a medium pan or wok over medium-high heat. Add 1 tsp sesame oil and heat until shimmering.
Add 250 grams (2 cups) shrimp to the pan in a single layer. Cook, stirring occasionally, until the shrimp turn pink and are cooked through (about 2–4 minutes depending on size).
Add 250 grams (3 cups) broccoli to the pan with the shrimp. Stir-fry together until the broccoli is tender-crisp, about 3–5 minutes.
Pour the prepared sauce over the shrimp and broccoli. Stir continuously until the sauce thickens and coats the ingredients, about 1–2 minutes.
Remove from heat, sprinkle with 1 tsp sesame seeds and the sliced green onion, and serve immediately.