Currently we have metadata based sink, as Alex Moser (@ptrdsh) hinted in a discussion one may want to access financial data from Cardano Smart Contracts. At the moment it is hard to think of exact use case for it but...
consider and evaluate what would it take to have plutus based sink, meaning we would store Transactions and Reports not as part of Metadata but as part of Plutus Data, which would make such data accessible to smart contracts.
Explore Charlie3 and OrcFax Oracles and observe if one can use existing Oracle standard wrappers.
CC: @cleanerm5 @Kammerlo @M4rc0Russ0