array-filter-map-ids.js

let A = [
  { _id: "34231555", status: "CANCELED", motif: "unable" },
  { _id: "1234551", status: "FAILLED", motif: "no number" },
  ,
  { _id: "1234455", status: "CANCELED", motif: "injoignable" },
];

let B = ["34231555", "1234455"];


// First, we filter only ids we want to update!
let filteredItemIds = A.filter(item => B.includes(item._id))

// Now update status and motifs based , C will the result of the update so the new reference you will need to use instead of A

let C = filteredItemIds.map(item => {
    item.status = "DELETED"
    item.motif = "Just deleted"

    return item;  
  })