Although we know that producing translations that are localized as specifically as possible depending on the particular locale of your intended audience(s) can be fruitful, many people find it may not be realistic to have their project localized for all of the different varieties of Spanish spoken in different locales. In 2010, Spanish was ranked number two in terms of the number of native speakers worldwide, falling second only to Mandarin. There are many different countries with Spanish speakers, and oftentimes, a company may want to release its product to an audience that spans across several of these different locales.
While each area has a different dialect, and therefore could require specific changes in the final localized product, it is not always within a company’s budget to go through this process for every locale. So, one might pose the question, “Is there a universal Spanish I can use? Something everyone will understand?” The answer to this is both “yes” and “no” and may also depend on the text itself.
Even though there may not be an official “Universal Spanish” dialect, there are certainly terms and phrases that are considered more "neutral" without the influence of local jargon or slang. The Real Academia Española, for example, strives to provide terms that are recognized by speakers of various dialects and does well to provide the standard definitions of words, as well as their various possible colloquial meanings, which may vary by country or region. For this reason, it is a good resource and starting point to localize a translated text into a Spanish that is somewhat universal.
However, it is still noteworthy to mention that the translators and editors of your content are influenced by their own respective countries and locales, which can inadvertently impact a word choice for even the most skilled linguist. They can work together to provide the most neutral Spanish possible, and a skilled team will provide a great rendition of the text with terms that are understood as widely as possible. There is always the potential that someone will read a translated word or phrase and not immediately recognize it as one they would use in their own dialect, but typically, context allows one to perceive the intended meaning.
In short, it is definitely possible to translate a text and localize it for a more universal Spanish overall. However, in doing so, there is no guarantee that the language team will not choose a term or phrase that is more commonly used in one area over another, despite its general neutrality. If you know that your target audience is specific to a few locales, it is best to let your translation project manager know so that he or she can ensure the finalized product is best suited for your needs. It may be the case that your text is better suited to a specific area, rather than trying to remain universal.