Is there a way to insert features from other styles into a style? I'm specifically looking to create a cascade-style SM but insert one slide with the wipe feature (a before-after comparison). Is that possible? If so, how?
Yes, you can embed story maps inside story maps. See: ArcGIS Blog: Embedding a Story Map within a Story Map
A useful alternative to embedding a Swipe app in a Cascade story is to add an immersive section in your Cascade and use one of the transition effects to provide a swipe-style transition between two different views in the section.
John Nelson on our team has created some useful 'How to Cascade' guides and one of them covers transitions. You can find them all here: ArcGIS Blog: See the "How to Cascade" Guides but in particular see this one: How to Cascade: Transitions.
Yes- first, create a new web app template that uses the swipe tool. Make that public and get the link for it. Inside your Cascade Story Map, add an immersive slide and then use the option to specify a URL. Paste the URL that you copied for the swipe tool web map app. If you'd like you can append "&embed" at the end of the swipe app URL to give a more seamless integration into your Cascade story map.
For example in this Cascade, click the Pinecrest Creek bookmark in the header after proceeding beyond the cover page, and then scroll down to the Historical development immersive section to see a nice use of the vertical transition between views containing images to present a swipe type before and after:
Connect the Drops in Pinecrest Creek
That same approach is also used in this example with web maps:
Mapping Distress in the Arizona Sun Corridor
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