Customer support in the customer's own language is one of the decisive factors for trust in a new market, especially for more expensive products and for services. Support exclusively in English is acceptable in some countries and, in others, significantly reduces willingness to buy. There are three solutions, and they can be combined. The first is a language version of the most common answers and documentation, which covers most questions without live contact. The second is assisted translation of communication, which can now handle routine matters as long as a person is available for sensitive cases. The third is a local partner or outsourced support for the given market. Don't forget time zones and stating your availability – a broken promise of a fast response does more harm than not making the promise at all.
See also: Response speed to inquiries, Localisation vs translation, AI for Small Businesses.