I swallowed semen and i want to have all remnants of semen and sperm removed from my mouth, how can i do this? if i use mouthwash will it clear out 100% of the semen/sperm? i want 100% no penis or cum in my mouth, is this possible?

Gargle with salt water and do it well and all remnants will be gone. Take your time.

Nothing will “clean out“ the presence of sperm from your mouth. I would recommend just drinking some liquids. Sperm will not live outside of the vagina, so pregnancy should not be a concern. Brush your teeth if it is a taste problem that you are having. You may want to discuss your concerns with your primary care doctor or gynecologist.