A few common misconceptions in this thread.
The QuadStrike anime isn't "made by Hasbro"; it is produced by the exact same Japanese team as the older seasons. Hasbro provided money for the production of another season and got their toys modeled by the Japanese animation team, similar to how Hasbro got Magma Ifrit in QuadDrive.
The QuadStrike toys are created the same as every other Hasbro toy; the Japanese designers make the TT toys first, then modify it by working with Hasbro. QuadStrike is no different; the Japanese designers created Burst Ultimate (BU) toys first, and then worked with Hasbro to make QuadStrike (QS) toys, and then showed these toys to the Japanese animation team who make the models for the anime.
Ex. Wind Knight (TT) toy -> Whirl Knight (Hasbro) toy -> Whirl Knight model in the anime.
On a side note, Hasbro exclusives are entirely designed by the Japanese TT toy design team, and Hasbro team modifies the design to fit their toys. This has been the case since the first season.
If 4th generation of Beyblade is coming, it is not surprising if there is no anime for the first year. Every generation of Beyblade starts off with no anime. More likely is TT just didn't see the point in spending money on a BU anime since anime does not increase toy sales in Japan the same way it does in the United States, which Hasbro has made clear several times in their fiscal reports.
Currently fan translating the Beyblade X manga. Beyblade Wiki Administrator and occasional manga scanlator.