Is it difficult for American visa couples to sign at the same time? Is it appropriate to sign twice?

The difficulty is the same. Couples are advised to apply for visas at the same window.

If the husband and wife do it at the same time, the chances will be even greater, because Americans think that travel should be enjoyed by the whole family, which is more in line with their routine. You can go together, but you can only go one by one when you sign face-to-face, and you can sign together when you travel. There is no need to separate.