That's a very simple test I made using GBStudio, a Zelda attack system based on the
GB/GBC Zelda game series.

Controls:

X (B): Attack
Up,Down,Left,Right: Move link (8-directions)
Enter (Start): Toggle music
Shift (Select): Restart the scene

When Link's health is full, he will do his sword beam attack.

Download

Zelda Sword Engine.gb 256 kB

Install instructions

This game can be played on any GBC emulator, you can play it using a Gameboy, but it's not recommended.

Is the sword shot as projectile or it's second sprite on map?

It's a projectile.

Thank you.