Is there any services which provide internal fund transfer? For example, imagine, I want to send 0.002 BTC to Binance from Kucoin. The fee is 0.0005 BTC which doesn’t make any sense to pay for 0.002 BTC. But if there is someone with an account in both exchanges can transfer to my Binance account from his Binance account, and receive slightly higher amount from my Kucoin account to his Kucoin account, the fee would be saved. I know this will be good for only a small group of people who actually are very small traders.
Is there any such services?
Coinbase, Xapo and Coinjar come to mind for same-platform fee free transfers, with Coinjar being an Australian firm so I'm not sure whether that would benefit you at all.
Pretty much, if a company offers a hosted wallet service whereby you do not control your own private keys, then it is very likely that they will offer off-chain transfers that incur no fees if done to another client.
But you'd have to balance the costs with the benefits. You forgo a degree of control over your own coins by doing this as you do not have control over your private key, and wallet-exchanges generally present less favourable exchange rates compared to actual exchanges themselves.
I'm not aware of any cross-platform services like this though (e.g. going from Polo to Bittrex without fees, or Kucoin to Binance). You could possibly negotiate on P2P channels if the exchange that you deal with have an off-chain transfer option, but that comes with an even higher counterparty risk.