Principia has a Latin characterset (see the overview below) which will cover most European languages. It also has some support for combining accents; so if the combination you need is not in the fonts, you might still be able to make it. Please let me know if there are glaring omissions and I will consider adding them! The fonts have some nice features described here.
IJsje & ijsje: jíj́?
This feature changes uppercase IJ and lowercase ij pairs into a curvy, single shape inspired by examples of Dutch lettering. A proper Dutch IJ with acutes is achieved by typing Iacute + J + combining acute or I + combining acute + J + combining acute
Hefð, fish, fünf
The lowercase f will generally try to avoid collisions and change to a shorter, shyer version of itself when there are ascenders or accents nearby. This shy f connects nicely with the next glyph. The only real ligature is an f-eth pair for Icelandic: this may not be the world’s most pressing typographic problem, but the shape is pretty.
All numbers are tabular, even the old style ones. Obviously the tabular width changes along the width axis, but you will figure this out. The lining numbers are at uppercase height.
Hyphen, endash and emdash, as well as a couple of friends like parentheses, braces and brackets (and some punctuation) shift up a bit to fit nicely next to uppercase.
There are some pretty arrows and a properly aligned fish. Accents are combinable and stackable. (In the variable version only)