You generally cannot directly broadcast a BTC transaction to miners without it entering the mempool, as the mempool is the standard, unavoidable gateway for transactions to be picked up and confirmed by the network. Bitcoin's design relies on the peer-to-peer network to relay transactions to nodes, which store them in their respective mempools before miners select them for inclusion in blocks. The only widely established method to bypass the mempool for most transactions is to use the Lightning Network, a second-layer protocol for fast, off-chain payments that only requires the main blockchain for opening and closing payment channels.