This isn't really a thing, not without huge visibility of the bitcoin network to correlate 'first time transaction seen'. Transactions are relayed by peers -- j

This isn't really a thing, not without huge visibility of the bitcoin network to correlate 'first time transaction seen'. Transactions are relayed by peers -- just because you saw some gossip from IP 'A' does not imply the transaction came from IP 'A', it could have been relayed through 'B' and 'C'. Furthermore, with dandelion routing, you cannot find the true origin of the tx by sight, even if you find the true first IP relaying the transaction.