You could check out this piece of CSS
https://sf.digital/squarespace-solutions/how-can-i-make-some-prices-poa-on-squarespace-71
If you want to hide the 'add to cart' button on individual products amend the code so that the description after the .tag- is something like hidecart and then tag whatever product you want to remove 'add to cart' with 'hidecart'. You can change this wording to whatever you like but always keep the .tag- part.
For example:
/* Hide the add-to-cart button */
.tag-hidecart .ProductItem-summary .ProductItem-details {
.sqs-add-to-cart-button-wrapper, .product-quantity-input {
display: none;
}
}
Hopefully my amendment should work. Thanks to SF Digital for the original code.
The answer is no. All templates have the same image functions for external links. I take it the option to "open in new window" toggle is not available in the image editor where you want to use a link? Single image blocks have that option toggle, images in a gallery do not. Also if lightbox is enabled for an image block the url link option is removed.