@hj1712,
Thank you for posting your requirements. It seems that the Aspose.Slides Cloud SDKs do not provide the features you requested.
We have opened the following new ticket(s) in our internal issue tracking system and will deliver their fixes according to the terms mentioned in Free Support Policies.
Issue ID(s):
SLIDESCLOUD-2072 - Replacing text in speaker notes
SLIDESCLOUD-2073 - Finding and replacing images by Alt Text
You can obtain Paid Support Services if you need support on a priority basis, along with the direct access to our Paid Support management team.