Questions like this come up here often, but I don’t have an answer for you. WC does not have clear documentation on how to add content like this to the checkout page. If you can find documentation to do what you want from WC and provide code that does not use ACF fields/content then I might be able to help you add ACF to it.
My answer, when it comes to WC, is to find a way to use what is provided by WC attributes and variable products. This is always what I have done.
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