For software that interfaces with Bitcoin Core via RPC, it can be useful to know whether the fRelayTxes flag is set. It could be added to `getnetworkinfo`.

if (pto->filterInventoryKnown.contains(hash)) {
                        continue;
                    }
                    
                    CFeeRate feeRate;
                    if (!mempool.lookupFeeRate(hash, feeRate)) {
                        continue;
                    }
                    if (filterrate && feeRate.GetFeePerK() < filterrate) {
                        continue;
                    }
                    if (pto->pfilter) {
                        CTransaction tx;
                        if (!mempool.lookup(hash, tx)) continue;
                        if (!pto->pfilter->IsRelevantAndUpdate(tx)) continue;
                    }
                    
                    vInv.push_back(CInv(MSG_TX, hash));
                    nRelayedTransactions++;
                    if (vInv.size() == MAX_INV_SZ) {
                        pto->PushMessage(NetMsgType::INV, vInv);
                        vInv.clear();
                    }
                    pto->filterInventoryKnown.insert(hash);
                }
            }
        }
        if (!vInv.empty())
            pto->PushMessage(NetMsgType::INV, vInv);