South Korea’s roller-coaster market, driven by sharp swings in semiconductor giants Samsung Electronics and SK Hynix this year, has also reverberated in Hong Kong, where suspected fund embezzlement by a loss-making investment manager and outcry from leveraged-product investors have made headlines.As an international financial centre, Hong Kong serves as a crucial gateway to access the Seoul stock market, with Futu Holdings – the Nasdaq-listed Chinese broker – just launching South Korea share trading and CSOP Asset Management’s leveraged product drawing strong interest.But as SK Hynix faces a brutal sell-off, investors are being warned about the risks of buying high-volatility semiconductor stocks on margin. The warning comes as CSOP’s Hong Kong-listed exchange-traded product (ETF) linked to the tech giant – known as CSOP SK Hynix Daily (2x) Leveraged Product – plunged more than 30 per cent on Tuesday. The downward trend continued on Wednesday, with the price dropping by up to 25 per cent at one point.The product surged to an all-time high of HK$193.65 (US$24.69) in late June, with its market capitalisation briefly surpassing HK$130 billion (US$16.57 billion) – making it Hong Kong’s largest ETP – before collapsing 80 per cent since the start of July.The sharp decline tracks a broader sell-off in South Korea, where the Kospi index tumbled more than 11 per cent on Tuesday, triggering its eighth circuit breaker this year. The index also fell below 6,000 points for the first time since April 14, and is now down more than 35 per cent from its June peak.Meanwhile, Hong Kong-based Futu has just launched direct Korean stock trading for users, who can trade over 2,700 Kospi and Kosdaq stocks – including SK Hynix and Samsung – without opening new accounts or exchanging currency, greatly streamlining access.