The Ohr Hachaim explains why the possuk needed to tell us the names of his sons, when the Torah already told us their names when they were born. He also asks why the Torah says עִמּוֹ – with him. There is no doubt that they went with them, Yosef took them.
Another matter of interest in this possuk is the repetition of the word אֶת.
The Ohr Hachaim explains that Yosef was explaining why he brought his children along with him. He wanted them to receive their Berachos separately to his brothers. He first brought them without his brothers, that they receive their Berachos. He also wanted them to receive their Berachos separately to each other, which is why the Torah repeats the word אֶת. Each bringing was a separate one.
They also had two reasons for which they deserved a Beracha. They were his children, for which they deserved a Beracha. This was the reason for them to receive a Beracha. Another reason is their personal merit, because they were Tzadikim. That is why their names are repeated and another אֶת is added.
