Modify MeshTopology with one button.

MeshTopologyModifier.cs

#if UNITY_EDITOR
using UnityEngine;
using UnityEditor;

public class MeshTopologyModifier : MonoBehaviour
{

    [SerializeField] SkinnedMeshRenderer[] m_skinned;
    [SerializeField] MeshFilter[] m_filters;

    private void Reset()
    {
        SetAll();
    }

    [ContextMenu("Go")]
    void Go()
    {
        for (int i = 0; i < m_skinned.Length; i++)
        {
            var mesh = CopyMesh(m_skinned[i].sharedMesh);
            Modify(mesh);
            m_skinned[i].sharedMesh = mesh;
        }
        for (int i = 0; i < m_filters.Length; i++)
        {
            var mesh = CopyMesh(m_filters[i].sharedMesh);
            Modify(mesh);
            m_filters[i].sharedMesh = mesh;
        }
    }

    [ContextMenu("Set All")]
    void SetAll()
    {
        m_skinned = GetComponentsInChildren<SkinnedMeshRenderer>();
        m_filters = GetComponentsInChildren<MeshFilter>();
    }

    void Modify(Mesh mesh)
    {
        int vert = mesh.vertices.Length;
        int[] indecies = new int[vert];
        for (int i = 0; i < vert; i++)
        {
            indecies[i] = i;
        }
        for (int i = 0; i < mesh.subMeshCount; i++)
        {
            mesh.SetIndices(indecies, MeshTopology.Points, i);
        }
    }

    static Mesh CopyMesh(Mesh mesh)
    {
        Mesh newmesh = new Mesh();
        newmesh.vertices = mesh.vertices;
        if (mesh.triangles.Length != 0) newmesh.triangles = mesh.triangles;
        newmesh.uv = mesh.uv;
        newmesh.normals = mesh.normals;
        newmesh.colors = mesh.colors;
        newmesh.tangents = mesh.tangents;
        if (mesh.boneWeights != null) newmesh.boneWeights = mesh.boneWeights;
        if (mesh.bindposes != null) newmesh.bindposes = mesh.bindposes;
        AssetDatabase.CreateAsset(newmesh, string.Format("{0}_{1}_{2}", AssetDatabase.GetAssetPath(mesh), mesh.name, "copy.asset"));
        return newmesh;
    }
}
#endif