So semantically... no difference.
It matters to those who care about this piece of literature. Maybe not as much as a lifetime of coital bliss missed, but who's to say?
What's up with the phrasing? Old English isn't a language that developed from Old Norse.
Beowulf was written in Old English, which is not a Nordic language.
> ... any of the speech patterns found in languages which developed from Old Norse.
Similarly, Old English didn't develop from Old Norse.
There may be a Celtic influence upon it as well, as with some of the Icelandic sagas, but you would have to dig much deeper for that.
Old Norse was a North Germanic language. Old English was a West Germanic language. They were mutually intelligible to a significant degree, since both were Germanic languages that evolved from the hypothetical common ancestor Proto-Germanic, but saying Old English was "90% a Nordic language" is like saying that humans are 90% chimpanzees. Both evolved from a common ancestor, one did not evolve from the other.
As for modern English, there are numerous Celtic loanwords and calques in American, Canadian and Australian slang and dialect.
But it doesn't make sense to say "such interjections were unlikely to be used by speakers of Nordic languages in order to begin a tale" without some sort of explanation for the focus on "Nordic" languages. Subsequent comments have made it clear that the commenter is under the mistaken impression that Old English was a Nordic language. It was not.