If your brand team lives in PowerPoint, Beautiful.ai is likely your best bet....

https://tango-wiki.win/index.php/Can_I_Generate_Slides_Directly_Inside_My_Existing_.pptx_File%3F

If your brand team lives in PowerPoint, Beautiful.ai is likely your best bet. I’ve spent years fixing broken layouts, but their PPTX export handles font substitutions surprisingly well