You can use map and replace
\[\d+\]$
\[– Matches[\d+– Matches one or more digits\]– Matches]$– End of string
var errors = [
  { name: "Emails[2]", message: "Email is invalid" },
  { name: "Role", message: "Role is required" },
  { name: "Role random [123]", message: "Role is required" }
];
let op = errors.map(({name,...rest})=>{
  name = name.replace(/\[\d+\]$/,'').trim()
  return {
    name,
    ...rest
  }
})
console.log(op)
solved Remove Index [number] from string [closed]