Is it possible to take 2 language B courses in IB?

[MarkWangM24]

I am currently considering taking Eng B L&L as an HL subject and Mandarin B L&L as SL, but I'm not sure whether it is allowed by the IBO as well as my school. From what i know, a number of students in China and HongKong do choose the combo above. Needless to say, studying their mother language at a foreigner level in Mandarin B is an easy peasy to them and that basically means they got straight 7s all the time without even revising.

However, I also heard some saying that the IB requires candidates to choose subjects from both group 1 and group 2 (only 1 LangA+1 LangB or 2 LangA is the available option). As far as I am concerned, if that's the case, it will be unfair for (for example) Korean students since usually schools don't offer Korean as an IB subject, and they'll have no choice but to take Eng A as their second language. This lack of clarification really confuses me a lot. In fact, I don't really care if unis will look down on me for doing 2 languages B subjects since my target major is not language-related and most unis focus almost entirely on HLs. So I would definitely go for this selection if it turns out to be a possibility. I'll deeply appreciate any comments and suggestions!