Thanks for your interest in Aspose.Slides.
Aspose.Slides does allow to access the font, color and other text related properties on portion level. One need to traverse each shape’s text frame and collections of paragraphs inside that text frame. Each paragraph has collection of portions.
I hope these links will help you in this regard.
Presently Aspose.Slides does not support styles like Aspose.Words. I have observed it as a new feature request. In order to assess the possibility of inclusion of this feature an issue with ID SLIDESNET-33142 has been created in our Issue Tracking System. Our development team will look into the possibility of implementation of the requested feature. This thread has been associated with this new feature request, so that you can be automatically notified as soon as this issue is resolved.
Thanks and Regards,
You are right that Aspose.Slide does not gives APIs related to getting slides from its internal name in case of .pptx.
An Issue with ID SLIDESNET-33142 is already logged for this new
feature in issue tracking system. Once our development team will respond you will automatically receive an email regarding outcome of this query.
Thanks and Best Regards.