Trump scenario:

A Trump win is more negative than a Clinton win is positive, and the downward pressure on EM FX is likely to be sustained for quite some time.

The currencies most at risk are those with large trade linkages to the US and where foreign policy issues are at play.

The MXN is in the eye of the storm and would immediately come under pressure, despite a lot of risk premium already in the price (evident in vol space, positioning, performance against oil and other EM currencies). It would immediately trade above 20 and could go as high as 23 Currencies such as the KRW, TWD and TRY would be the next ones in the firing line, impacted through several channels (trade, security, sentiment, local factors, and US rates) - link

Our favorite Trump hedge owns a USDTRY call with a topside knock-out.

Clinton scenario:

A Clinton win would translate into a modest and transitory relief rally in EM currencies - the exception being the MXN which should meaningfully strengthen. Unlike a Trump victory, a Clinton win is not a major catalyst for investors to re-evaluate their EM thesis.

The risk sentiment channel is likely to be the strongest driver of currency moves, particularly immediately following the election result (link). USDMXN may trade down to 17.5 in the ensuing days as the significant risk premium related to US elections is unwound.

High-beta currencies such as the BRL and ZAR are likely to benefit, while the currencies with the most to lose under a Trump presidency would show some gains (KRW, TWD, and TRY).

Having mentioned that, MXN would likely outperform the rest of the EM currency complex.