bullet follows target and arcs with sin

Hello,

I have a bullet that must follow player and rotate bullet graphics so that bullet appears to move forward.

I do this like this:

 transform.rotation = Quaternion.LookRotation(Vector3.forward, transform.position - _target.collider2D.bounds.center);
     transform.position = Vector3.MoveTowards(transform.position, _target.collider2D.bounds.center, flySpeed*Time.deltaTime);

what I want to achieve now is that bullet does not move in a straight line but sort of arcs up and down while tracking the player. Sort of like a sine movement applied to it.

I managed to do that with this code:

         transform.rotation = Quaternion.LookRotation(Vector3.forward, transform.position - _target.collider2D.bounds.center);
        Vector3 _targetRotation = transform.eulerAngles;
         float _rotationAddon = Mathf.Sin (Time.realtimeSinceStartup)*sinSpeed;
        _targetRotation = new Vector3(_targetRotation.x, _targetRotation.y, _targetRotation.z+_rotationAddon);
         transform.eulerAngles = _targetRotation;
 

But when I use this I can't find a proper movement code that will move the bullet forward based on angle and does not look weird if it has to turn 90+ degree angles when tracking the player.

has anybody done something similar?

Thanks in advance