The big brass coins returned two year after their initial release, though there were some changes.
The 1990 set was put out by a company called Ban Dai. The 1992 release came from a different company, Diamond Promotions.
It looks like Diamond bought out the remaining stock of the 1990 coins and repackaged them.
It must have been somewhat of a success for them because in 1992 they put out their own set. They use the same dies as Ban Dai with a couple modifications. Diamond didn't obtain a license from MLB, so the team logos were removed. A player's association logo was added.