
Hello,
Welcome to Microsoft Community Forum.
As per your description, Emphasis animations function correctly in the desktop app but do not appear in the web version.
This is because certain emphasis animations, such as darkening text or changing object colors, may not be fully supported in PowerPoint for the web. The web version has a limited set of animation effects compared to the desktop app, which can cause inconsistencies when viewing presentations online.
Hope this information addresses the issue you are facing.
Regards,
Matt | Microsoft Community Moderator