If your target audience is English speakers, then employ a native English-speaking writer who can write the content in perfect 'marketing' English. Interesting, informative, persuasive and SEO-aware - that kind of thing. Anything less and your content will be third-rate - and what is the point of publishing third-rate content in a competitive market?
Unfortunately there are many websites written in 'English' by people who can't actually write good English, often because it is a second language. English speakers can spot this a mile off, and it can be quite distracting to many people in the target audience. And that can never be a good thing.