Board Thread:Theories and Speculation/@comment-45444155-20200804084623/@comment-4080775-20200805113406

It's not accepted, you just read it wrong.

Black Zetsu was never a Truth-Seeking Ball. Obito just imbued him with Six Paths Chakra and "shaped" him in a manner similar to a Truth-Seeking Ball.

The user can use Shape Transformation on the TSB to change its shape and nature, just as they can use it on normal natures and do the same.