Have you tried the US-International layout[0]? It's basically the standard QWERTY US layout but ", ', ^ are dead keys used to generate diacritics.
If you press " followed by o you get ö.
' + e prints é.
The only thing to get used to is that if you want quotes for example, you need to press <space> or another character that doesn't accept accents after the key. I used this layout for French and it's way better than the weird French AZERTY layout.