Is there a template I can download for this 4 x 6 card?

We do offer free templates on the product page. You can scroll down the product page below the customer reviews to view the available options or visit the link below. https://www.onlinelabels.com/templates/blank/ol959

Is there a variant of this label with a radius cut on the corners? The only other 4x6 option with that is a single label on an 8.5x11 sheet

I apologize but we do not have a rounded corner 4" x 6" label on an 8.5" x 14" sheet. If you require the rounded corners, we can create a custom configuration for you. You can request a custom label on a large format sheet by visiting the link below or contacting Customer Support at 888-575-2235. https://secure.onlinelabels.com/Support/LargeFormatSheetRequest.aspx

When you say "clear" does this mean transparent?

The Clear Matte Inkjet (CJ) material has a frosted finish, so it will be translucent. If you're seeking a fully transparent label, I recommend our Clear Gloss labels. You can request samples of our clear labels through the link below for testing with your application. https://www.onlinelabels.com/samples

Can these labels be used for freezer use?

The True Red (TR) is a paper-based material with a standard permanent adhesive and is not moisture resistant. For freezer applications, a weatherproof option would be recommended: https://www.onlinelabels.com/materials/weatherproof-labels