It would not be a bad idea to have some kind of Standard English for international use. As far as I know, such attempts did occur in the past.

Around the time of World War II, someone came up with the idea of Basic English. The idea was an abysmal failure, but I can see why: It was supposed to be a subset of English using a select number of verbs used in combination with modifiers, such as up, off, in, etc. Such combinations are very common in English, e.g., put up, give in, and such. Unfortunately, they also are the hardest part of the English language for non-native speakers to master. The idea was naive (despite it being pushed by Churchill), and could never survive.

A Standard English would have to be the full English language, not a subset. There would need to be some kind of agreement about its vocabulary, i.e., each word would need to be used in a way everyone understands as opposed to regionalisms. E.g. soda would be preferable to pop.

The greatest obstacle, given the nature of English would be standardized pronunciation. By that I don't mean phonetic alphabet, rather the same word is pronounced the same way by everyone (e.g. potatoe, either...).

For it to succeed, it could not be forced as a replacement of regional types of English. Rather, people should be allowed to continue speaking as they do, and only use the Standard English when communicating on an international level.

Systems following these principles do exist and are successful in other languages. China may be a prime example: Each province speaks pretty much a different language, but all school children are taught Mandarin, so they have a common language to talk with people from other provinces.

Indeed, Transatlantic already exists and is used as an international (or perhaps "metanational") dialect of English. But only by actors. For it to become a truly Standard English, it would have to be taught to school children with the clear understanding it is not the one and only correct way to speak, but the accent/dialect to be used in international conversation only. It would also have to become the standard dialect to teach English as a second language.

It is quite possible for you to pick up Transatlantic. All you really need is to study Teach Yourself Transatlantic, by Robert L. Hobbs, then practice, practice, practice. Unfortunately, the book is out of print, but you should be able to get a copy through interlibrary loan. The drama department of your local college may have a copy as well. For that matter, they may even tutor you (it is much easier to learn an accent from a live teacher than from a book).

One nice thing about Transatlantic is that it is not a native dialect of any place, so no one would feel why should I talk like people in XXX.