Btc transaction accelerators not working? Hmm, I was going to suggest it right now. No they work, tu be fair only one works and that's viabtc's free transaction accelerator which is so spammed that it makes nearly impossible to include your transaction in 100 free tx list. But op if you can to do everythinf in less than a second, just send any transaction with 0.0001 btc fee and it will get confirmations by helping of viabtc. There are no other chanses if you don't use wallets with local offchain transfers.