nawk '
NR==FNR { c = a[$1]; a[$1] = c?c" "$2:$2; next }
{ c = a[$1]
  if (c) {
    split(c,b)
    for (k in b) {
      p = $2<b[k]?$2" "$1" "b[k]:b[k]" "$1" "$2
      if (!d[p]++) print p
    }
  }
}
' file1 file1