It is rather obvious the neither Jim or Tim from Microsoft actually use Excel, or they would know the answer to your question. I wish Microsoft would limit Microsoft "Agents" to questions to people who use the products they support.
The new chart types are now available because the 16.9 update brought the Office Object model up from version 14 (from 2010/11 era) to the same object model as Office 2016 for Windows. It's a huge leap forward for Office for Mac.
Bringing the Office 16 object model allows Microsoft to enable features in Office for Mac that were Windows only. We now have the missing formulas, charts, PivotCharts, etc we've yearned for over the years. We'll probably get the Power features at some point,
too.
This brings a big challenge to Microsoft in that they have to build the interface of Office for Mac to support all the new underlying code. I just did a quick test and recorded a macro while making a Histogram. Recording works. This leads me to think that
VBA for formatting charts is likely to be all hooked up and working. If you know VBA, you should be able to use it to format the new chart types.
If you want to be among the first to get new interface features, you might consider signing up for Insider Fast. Insider Fast builds are pre-beta, large, weekly builds having undocumented new features and new bugs to report.
What is Office Insider? - Office Support
In 16.10, the Ribbon has placeholders for formatting options, but they don't fill in. The format pane does not display for new chart types. I am sure these will be built in the coming weeks and months. I find it exciting to watch as they add the new functionality
to the interface, but I can see why it might be a drag or disappointment if you want these things right away. Microsoft decided to let us have as much as they can at the moment. I'm happy with that decision. Otherwise, we wouldn't have the new charts to work
with at all until the whole interface was finished.