"Professional formation" (formación profesional) implies the shaping of a scholarly/critical identity and a process of graduate professionalization. In both French and Spanish this is sometimes referred to ironically as "déformation professionelle" / "deformación profesional," the idea being that the personality is not only shaped but actively deformed.

Think of how the body itself bears the marks of a given profession. Now analogize that to the mind. What does a librarian's body look like? A bullfighter's?

The idea is that all of one's readings and graduate courses are formative of identity. You are not just learning new information or new sets of skills, but being shaped into academics. (The process of emulation referred to in a previous post is part of this process.)

You will learn to "think like a professor." That differs quite a bit from the goal of undergraduate education in the humanities, which is to provide some critical thinking and writing skills, along with some limited concrete knowledge of a particular field.

Now you might also absorb, along the way, some of the typical prejudices of the academic. For example, critical work is more highly valued than translation or so-called "creative" writing; certain types of critical work are seen as more valuable than others, so that an encyclopedia article is seen as less significant on one's resumé than a critical article. Articles that are merely "descriptive" are less prestigious than those that are "theoretical." Articles on teaching or pedagogy can be looked on with suspicion at times. I won't urge you to adopt those prejudices enthusiastically. I would say that the best approach is to be aware of them and of the reasons behind them; be aware of the consequences of being unaware of them, but don't let yourself be deformed by them.

For example: it can be a bad idea to publish a not-so-great paper in a second line journal as a grad student. Or an encyclopedia article as an assistant prof. You don't lose much by following the prejudice in these cases and putting your time to better use. On the other hand, if you have a really innovative approach to translation and think you can make a mark on the field in that way, that might be something you should go for. You might be the next Ernesto Livón-Grosman or Gregory Rabassa.