I tried many ways of disabling crux i.e

"mysticalagradditions:nether_star":
{
      "crux": "none"
}

"mysticalagradditions:nether_star":
{
      "crux": false
}

"mysticalagradditions:nether_star":
{
      "crux": null
}

Please help me, I have been trying to figure this out, I am almost going to try minecraft:air

The next release will allow this by setting the crux to null. You will also need to update to the latest version of Mystical Agradditions.