Hohner B2B bass - is this real model - not listed on history?

The B2B bass is not listed in their own database:

I came across what seems to be a Hohner B2B with model number 02054318. Just trying to learn more about the specs and when it was made.

Is this a real Hohner bass or why is it not listed there on that list?

As you can see from that list, Hohner produced a vast number of guitar models over the years. The list makes no claim to completeness. If the instrument you mention carries a Hohner logo and is a headless bass then it will presumably be authentic.
FYI in 1985 Hohner acquired the exclusive license from Ned Steinberger to build several headless models using his designs. The basses in particular are highly prized today and always offered good value for money.
I’ve asked Hohner Service if they can provide more info and will post here when I have a reply.

They say this bass was built in Korea in 1990 and is definitely the genuine article.

Thanks! Is there anyway to know what the specs are for the ones built in that year?

Sorry, I don’t think there’s more information available.