Second Product variant image in fb share is not coming I am using [node:field-product:0:field_images] metatag image.
With which I am getting top level variant image always. How can I get my second product variant image in facebook share, when I select second product variant from the variant selection dropdown on product display page.
[node:field-product:1:field_images]


You'd add that in your metatag image field together with the first token that you mentioned, separated by comma.

If fb is still not picking it up, after your fetch new scrape info, try adding :file:url to your tokens. 

[node:field-product:0:field_images:file:url],[node:field-product:1:field_images:file:url]