Apparently, there are regular correspondences between Swedish ö, Old Norse au, and Old English ēa (which is sometimes preserved in modern English spelling, though the pronunciation has changed).
From the table on that page, it's interesting to see how many German words also have au (together with Old Norse) and so are likely also cognate with the English words in the table... words where I would not necessarily have made the connection.
Specifically, Saum/seam; Traum/dream; Zaum/team; laufen/leap. The first two connections are easier to make since the meanings are much the same, though I wouldn't have thought that would be a regular sound correspondence; the next one is harder since the primary meaning of "team" for me is in sports or work, with "team of oxen" only being a secondary meaning, though even that's not that close in meaning to "rein". And "laufen/leap" is probably not a pair I would have come up with myself, either, due to the difference in meaning (run vs. jump) and the consonant change. Oh, and Lauch/leek.
Some German words have o, though (e.g. hoch, Ost, Brot, tot, rot); I wonder why that is. Maybe also the cognate of "auðr"; given the gloss "wealth/property" for the Old English cognate, I wonder whether the second part of German "Kleinod" is cognate.