The reason why it's #TimeForTonnika is that, from a super articulated tooling perspective, we're:
The timing is almost uncanny. Over 70% of the parts from the VC157 - Zorii Bliss figure can be re-used to create Tonnika sister figures. There is quite a disparity in heights between the two sisters, but this could be mitigated by creating slightly varying lower torsos and differently sized discs used for that point of articulation.
Hasbro closely guards how many of each figure are produced, and whether or not those figures are profitable. Having said that, it's hard to believe that the return on investment for the Zorii Bliss tooling was that great. The Rise of Skywalker Vintage Collection wave seemed to barely ship. Hasbro can recoup some of that investment by immediately re-using some of the tooling on Senni and Brea.
Hasbro would only have to tool two new heads, two lower torsos, one new hip, and one set of upper arms in order to make two highly requested fan favorite figures. It's almost serendipity. Underutilized tooling is languishing that could be put to immediate reuse. Now is the #TimeForTonnika before those tooling assets get lost or degrade.