FYI: there are quite a lot of queries on the internet about Excel crashes (also reported by the Event Viewer as caused by OART.DLL) when trying to format a chart's axis e.g. via context menu.
Here's a solution that worked for me (in my case: Excel2010 x64 on Windows10 Home x64 with a spreadsheet containing a xy scatter chart and x axis representing time/date values):
Ensure that Windows => PC Settings => Date & Time => Region => Languages **AND** Windows => Control Panel => Region => Formats **AND** Excel => Options => Language have consistent non-contradictory values when you have language packs installed. Ensure same uniqueness for time/date default formats.
When adapting any values to a consistent state, it's probably best to reboot Windows / restart Excel.
As I've spent hours in searching for a solution to those CDTs, and as Internet searches have not returned a functional fix, I hope this hint will help others searching in vain as I did before troubled by the same problem.
Cheers - Robert