Glad I could help 
Topic summary
Secondary product image on hover in the Berlin theme’s collection grid wasn’t working despite the built-in setting being enabled (Online store > Themes > Customize > Collections > Default collection > Product grid > Show secondary image). A screenshot was shared to indicate where to toggle this option.
Enabling the setting alone did not produce the hover effect. The fix was to edit the theme.liquid (Shopify’s main layout file) and add a custom code snippet immediately after the tag; after this change, the secondary image appeared on hover.
A follow-up request asked to make the homepage slider image clickable without displaying the large overlay button. The solution was another code addition in theme.liquid, which achieved a clickable slider image as desired.
Code details were not included in the thread (the code blocks showed as placeholders), but both issues were confirmed resolved after these edits. No further action items or unresolved questions remain.