Sorry bro. But how can a 30% premium not be profitable? Someone from lets say Australia (10% premium) can send me unlimited amounts of money for very good exchange rates and small fees. How can this not be profitable. With xrp we are talking about 2 minutes transaction time. Trading involves risks. Arbitrage is much more safe volatilitywise. It has a expected value you can calculate. The only risk is the human. Like always . You can not open accounts on korean exchanges and withdraw fiat. Only a Korean can. It is 100% legal for him to do this with you as long as he not sends more then 50k usd overseas per year. All you have to do is find a trustworthy Korean. And as Koreans are generally very well educated, behaved and crypto affine the chances are high of getting to know someone who is legit.
Especially if he is vouched for. And just for the record. I`m doing it already with 5 people (2 are privat friends I personally know) and it is profitable. Of course I can not risk to roll too much money in one sending because of obv risk managment reason but overall it is very profitable equity wise.