In my work as a translator, I have come across these terms being used interchangeably. Given that being a translator is often carrying out detective work to find correct phrases and terminology (my biggest challenge was translating the technical specs of a warship!), I have been doing research, and these are examples of what I have found
My favourite so far (from which the header image comes) is this article.
It seems that many people are using the word digitisation when they mean digitalisation or digital transformation. Businesses that move away from brick and mortar to being app-based are an example of digitalisation. Or?
An interesting postscript: Because my translation work is from Swedish to English, and mostly within the EU, I am required to use British spelling because that is the official language in which I work. I would actually prefer using organization rather than organisation, and labor rather than labour for example, because that brings up more hits in search engines and draws more visits to websites, but rules are rules. I sometimes try to argue that if a concept comes from the US the spelling should stay in American English, but language purists definitely do not agree.
Being a translator (and an interpreter) myself I so well understand what you mean with the “detective work”. Researching phrases and terminology is one of the reasons why I love that job.
Being an interpreter is totally different though as you are not allowed further research once the prep work is done and we work more in the emergency of the action.
As for the choice between British or American English I don’t really mind. The official language in which I work is British English and I find it quite natural for me after all these years of translating/interpreting.
I have the same dilemma with European Spanish and the American Spanish. At the EU we mostly use European Spanish but some of my colleagues would prefer American Spanish when we are dealing with South American matters. It would sound more natural.