I'd like to know how to enable the ordering service of Hyperledger Fabric for exchanging messages among these kind of nodes. For instance, if only these nodes have to compute a result together but everyone has only one part of the input, is it possible to allow them to exchange this partial input and compute the result as output in order to send to an application client afterwards? I know that ordering service is used to order transactions and to enable the broadcast of validated blocks among other peers but I'd like to know if this kind of customisation is granted on this platform.
No. Orderer nodes do not "compute results". Only endorser peer nodes do.