Not really sure what you mean by instant transactions, but maybe you can refer to this table,
https://www.makeuseof.com/bitcoin-is-slow-what-is-the-fastest-cryptocurrency/
However, take note that we are talking about blockchain technology, so everyone should be written first before the transaction can get through and that is the essence of it. Be immutable and so that there will be no questions about the transaction itself.
now that's the point, everyone has to queue to wait for their transactions to be written on the blockchain because the blockchain is a ledger that is the data center for all transactions, without confirming a block it cannot be done. The denser the network, the longer it will take. For example shopping and wanting to pay at the cashier with a long queue. Direct transactions may be possible outside the blockchain, but if you expect crypto like that, then the crypto ecosystem will be useless and the blockchain will not be used.https://www.makeuseof.com/bitcoin-is-slow-what-is-the-fastest-cryptocurrency/
However, take note that we are talking about blockchain technology, so everyone should be written first before the transaction can get through and that is the essence of it. Be immutable and so that there will be no questions about the transaction itself.