Clash of Sword RigidBody2D

Hello Everyone!
I want to make two "sword" hit each other and the players step back or just repel each other. I couldn't find any solution, except pointeffector2d. But, this effect is not what I want.
I have a boxcollider2d as a trigger, circlecollider2d also as a trigger (both in front of my character) and a rigidbody2d. The parent (is the character) also have a RigidiBody2D and other colliders and gravity of 5.
When I hit X button, start the animation and the boxcollider2d and the circlecollider2d are enable until the end of the animation.
The reason I use a trigger is because the player could be closer to the enemy, and the sword can hit the enemy and not just "air" or empty space. Also, if is not a trigger, when the colliders are enable and hit the enemy rigidbody2d, have a random behavior.
I find a similar code and I thought could be useful, but didn't work

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class colliderAttack : MonoBehaviour
6.  
7. public float force = 300f;
8. public bool hasHit = false;
9.  
10. void OnTriggerEnter2D (Collider2D swordAttack)
11. {
12. if (swordAttack.gameObject.tag == "Sword" && !hasHit)
13. {
14. hasHit = true;
15. StepBack();
16. }
17. }
18.  
19. void StepBack()
20.     {
21.         CircleCollider2D collision = gameObject.GetComponent<CircleCollider2D>();
22.         if (collision.gameObject.tag == "Sword")
23.         {
24.             Vector2 dir = GetComponentInParent<Rigidbody2D>().transform.position - collision.transform.position;
25.             dir = -dir.normalized;
26.             GetComponentInParent<Rigidbody2D>().AddForce(dir * force, ForceMode2D.Impulse);
27.             Debug.Log(dir);
28.         }
29.     }
30.  

If someone could help me to find a solution or give me a better way to do the clash of sword I will be grateful...
Thanks!!!