There is no real trend. In my experience it depends upon the author of the document and upon the aims of the document.
If a European business is preparing a document for use in a variety of English-speaking markets then they usually use American English. If a document is targeted at a specific market they use the form appropriate.
If no specific target or decision is made, I have seen documents written in whichever version of English is most comfortable for the author. This depends on how they learnt.
Academic works usually have to comply with the style guide of the publisher. Most academic journals have quite detailed style rules which are imposed upon articles and papers that they publish.
As for EU documents, I am not aware of any EU directive, but the English forms of most EU documents are prepared by British citizens which may affect the outcome.
If your question is intended to ask which version you should use in an upcoming document, I would check if there is a style guide to which you should comply. Otherwise do as you think best.