I stick with the Greek. I show English translations because most don't know Greek. I end up with preferences based mainly upon what I see in the Greek.
At least the KJV is honest in italicizing where it makes insertions as it did with the addition of "the gospel" the second time. IMO the translations that did not insert "the Gospel" the second time are the best to start with because that second time is not on the Greek.
There re: up to 30+ ways "of" (which is a very effortless fall-back translational insertion and interpretation) can be translated. "of" is basically ambiguous and begging elaboration. You can look at an English dictionary definition for "of" and see even the range of meanings in English.
I had this site on my screen from another discussion where it was raised for me to consider. Here's what A.T. Robertson said about Gal2:7-8. He's providing the basic translation using "of" and then interpreting it. When he speaks of "sphere" and "type" re: 2:7 he's analyzing the "of" in regard to the 30+ choices I mentioned. So, he says there are 2 different Gospel spheres and not 2 different Gospel types. As he clarifies, it is the same Gospel. Underlines are mine:
Here's the link:
Galatians 2 - Robertson's Word Pictures in the New Testament - Bible Commentaries - StudyLight.org
Gal2:7
That I had been intrusted with the gospel of the uncircumcision (οτ πεπιστευμα το ευαγγελιον της ακροβυστιας). Perfect passive indicative of πιστευω, to intrust, which retains the accusative of the thing (το ευαγγελιον) in the passive voice. T
his clear-cut agreement between the leaders "denotes a distinction of sphere, and not a difference of type" (Lightfoot).
Both divisions in the work preach the same "gospel" (not like Galatians 1:6, the Judaizers). It seems hardly fair to the Three to suggest that they at first championed the cause of the Judaizers in the face of Paul's strong language in verse Galatians 2:5.
Gal2:8
He that wrought for Peter unto the apostleship of the circumcision (ο γαρ ενεργησας Πετρω εις αποστολην της περιτομης).
Paul here definitely recognizes Peter's leadership (apostleship, αποστολην, late word, already in Acts 1:25; 1 Corinthians 9:2)
to the Jews and asserts that
Peter acknowledges his apostleship to the Gentiles. This is a complete answer to the Judaizers who denied the genuineness of Paul's apostleship because he was not one of the twelve.
I've already posted quite a bit of work re: Paul's full message in Acts13 c.f. 1Cor. I see no need to answer questions that do not interact with that work compared with the work I posted on Acts2.