Strafe jumping is not possible in Call of Duty: Modern Warfare (2019) on any platform, including Xbox 360 (which didn't receive this title—MW 2019 is PS4/Xbox One/PC only).
Strafe jumping **works**. Technique: Jump → Hold Strafe (A/D or Left Stick Left/Right) → Move Mouse/Right Stick same direction → Jump exactly on landing → Repeat. Requires 125/250/333 FPS (physics tick rate) for max gain—console locked at 60 FPS makes it weaker but functional.