Global markets were sent sharply lower this week, as fears of a trade war sent shockwaves across global financial markets.

Amid the turmoil, some market participants think emerging markets are a value play to consider. Ed Keon, chief investment strategist at QMA, said developing economies' stocks are a good buy, even in the midst of short-term headwinds.

Earlier this year, Keon took down some of his overweight position in U.S. equities, and upped his exposure to emerging markets.

"After underperforming for several years in a row, and having a decent year last year, emerging markets still look like pretty good values for us. So we are overweight emerging markets across our multi-asset portfolios," Keon told CNBC's "Trading Nation" on Friday.

Looking at classic metrics like price-to-book ratios, and trailing and forward price-earnings ratios, Keon said that emerging market equities present a better value at these levels than those in the U.S.

One large emerging markets exchange-traded fund, the EEM, carries a forward price-earnings ratio of 12.4; that compares to 16.5 on the S&P 500 Index. The EEM, comprised most heavily of Asian equities like Tencent, Samsung and Alibaba, and in 2017 posted its best year since 2009.

"Across the various metrics, emerging markets look cheaper. They always look cheaper compared to other established markets, on raw measures," Keon said.

"But even adjusting for their normal discounts, I think you get better value, generally, in emerging markets than you do in developed now," he added, referring to the relative risk emerging economies sometimes carry relative to more established markets.

Keon contended that while the prospect of rising interest rates in the U.S. stands to hurt emerging market equities in the short-term, the broader issue is whether a global trade war will break out.

Just as in essentially every corner of the global equity market, Keon said, "there has been a new bout of uncertainty so far this year. But I think when you net it all out, I think the story for this year will be the great rise in earnings in the United States and global growth overall.

He added: "I think you'll see that equities will end up having a pretty good year, but clearly right now there is a great deal of uncertainty in the market."