You can assign an empty object {} as default param value to it. Wrapping object param type with Partial to make its memebers optional, same as adding question mark { objArg?: string }

const func = (arg1: string, { objArg = true }: Partial<{ objArg: string | boolean }> = {}) => {
  console.log(objArg)
}

You can set an default value and it will be automatically optional:

const func = (
  arg1: string,
  { objArg = true }: { objArg: boolean } = undefined
) => {}

If you want to make an parameter optional, you should use ?(question mark) before :
and optional parameter has to be the last parameter of function. For more information check this page. https://www.typescripttutorial.net/typescript-tutorial/typescript-optional-parameters/