At the 1932 Summer Olympics, India defeated the USA with a score of 24-1.
Is this match the highest scoring match ever at international level (no domestics)?
Has any other country defeated their opponent by 20 or more goals?
Here somebody states:
I couldn't verify that.
However, while looking for verification I did find this:
I assume that this is Samoa, the nation.
And then I found this.
Papua New Guinea (men and women) were beaten with monster scores by New Zealand and Australia, including
For other contenders, you might want to check each of these.