Is that this the payment per output or for all the transaction?

The payment is per transaction not per output. Within the community knowledge it’s merely sum of enter quantities – sum of output quantities.

Is it cheaper – and if that’s the case why – to ship transactions with a number of outputs?

The creator of a transaction is utilizing the payment to bid in an public sale of house within the subsequent block. Subsequently the payment is predicated on the scale of the transaction in bytes (or in vbytes for segwit transactions). That is typically known as the burden.

Since each transaction wants a header and not less than one enter and often a change output header, you save on repeating the byte sizes of those by combining many business transactions into one Bitcoin transaction.

HIOOOOOOC “weighs” lower than HIOC+HIOC+HIOC+HIOC+HIOC+HIOC. Subsequently it prices much less.