How do I apply lambda to each item in a loop?

I have this snippet saved as a lambda function:

const accentedCharacters = 'áàãâäéèêëíìîïóòõôöúùûüñçÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÕÔÖÚÙÛÜÑÇ'

const normalCharacters = 'aaaaaeeeeiiiiooooouuuuncAAAAAEEEEIIIIOOOOOUUUUNC'

let text = $var.sample.replace(/[áàãâäéèêëíìîïóòõôöúùûüñçÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÕÔÖÚÙÛÜÑÇ]/g, match => normalCharacters.charAt(accentedCharacters.indexOf(match)))

return text

I wanna use it inside a loop to update each item. Example, I'm looping through a list and wanna use this lambda function to each item in that list. I tried using map

const accentedCharacters = 'áàãâäéèêëíìîïóòõôöúùûüñçÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÕÔÖÚÙÛÜÑÇ'

const normalCharacters = 'aaaaaeeeeiiiiooooouuuuncAAAAAEEEEIIIIOOOOOUUUUNC'

return $var.r2array.map(item => {item.sample = item.replace(/[áàãâäéèêëíìîïóòõôöúùûüñçÁÀÃÂÄÉÈÊËÍÌÎÏÓÒÕÔÖÚÙÛÜÑÇ]/g, match => normalCharacters.charAt(accentedCharacters.indexOf(match)))

return item.sample})

however I keep getting this error:
['$auth must be an object','$var must be an object','$env must be an object','$input must be an object','$global must be an object','code must be a string']

How do I fix this?