Even though there is not an out-of-the-box option for modifying a no-results page, the InstantSearch results page is quite customisable (even when there are no results returned).
Here are a few points of reference/documentation that should be helpful in your customisation:
- Handling No Results with InstantSearch hits 'empty' template.
- Customising the InstantSearch Results Page in Magento (this references the
hitswidget mentioned above) - How do I handle no results pages? (in addition to some of the information above, this guide also provides insights into avoiding searches that return no results)
You can also implement Algolia's Query Suggestions feature and then enable the automatic population of suggestions on a "No Results" page by toggling the "Show query suggestions when no results" setting in the Magento Admin (Algolia Search > Instant Search Results Page)
