A Shulker hitting a Shulker with a Shulker Bullet can not make a new Shulker. (Vanilla parity)

With the full release of 1.17 Java Edition on June 8, 2021 the following change was made:

• A Shulker hitting a Shulker with a Shulker Bullet can make a new Shulker

This feature has been absent from the Bedrock edition since its introduction & has remained a Java exclusive feature.