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Yes, for strategies with low enough transaction costs (i.e. for most buy-and-hold like strategies, but not day-trading).
It will be somewhat hard for ordinary investors to implement the inverse strategies, since brokers that cater to them restrict which stocks they can sell short (professional investors usually don't face this problem).
The EMH is only a loose approximation to reality, so it's not hard to find strategies that underperform on average by something like 5% per year.