JS match skus

let a = [{"sku":"a"},
{"sku":"b"},
{"sku":"c"},
{"sku":"d"},
{"sku":"e"},
{"sku":"ff"},
{"sku":"gg"}]

let b = [{"sku":"k"},
{"sku":"z"},
{"sku":"d",'fig':3},
{"sku":"b","fig":5},
{"sku":"a"},
{"sku":"c"}];

let __KEY__ =  Object.keys(a[0])[0]

a.forEach((x,i)=> {
  let k = b.find(z=> z[__KEY__] == x[__KEY__])
  if(k) {
    a[i]._MATCHED = k[__KEY__]
    a[i] = {...a[i],...k}
  }
  });

  console.log(a)