I just wished there could be something easy to replace this equation editor, it's really smooth for people that are not really proficient with LaTeX
In PowerPoint, I am a happy user of IguanaTex [1].
There are also some other PlugIns like TeXsword. But I have not tested them. And newer MS Office versions seem to support Latex macros directly. [2]
[1] https://github.com/Jonathan-LeRoux/IguanaTex
[2] https://support.microsoft.com/en-us/office/linear-format-equ...
How about Eric Lengyel's equation editor: https://radicalpie.com
Microsoft wrote their own replacement and it's better-integrated into Office than the old editor was. Search for "insert equation" in the Office search box. The new one supports both the old editor's style of input and actual LaTeX inputs. Heed the dates on articles talking about it: TFA is from 2018 before they wrote the new editor.