Can I choose which European country my IPs are located in

Yes. The European pool is not a single undifferentiated block, and you pick the location when you order. The countries currently available are Sweden, the United Kingdom, Germany, the Netherlands, France, Italy, Poland, Finland and Denmark, which gives you a second axis of separation on top of the block-level diversity itself.

Two kinds of separation at once

Block diversity scatters your sites across the address space. Country diversity scatters them across jurisdictions and routing paths. They are independent of each other, and using both makes an estate considerably harder to describe as one operation than using either alone.

An estate whose addresses all resolve to one country still shares a fact, even when the blocks are unrelated. Spreading across nine possible locations removes that shared fact without costing anything extra, which makes it one of the few genuinely free improvements available.

Choosing per site rather than per estate

The useful mental model is to let the site decide rather than picking one country and applying it everywhere.

• Follow the audience. A German-language site on a German address is a coherent arrangement. The same site on a Finnish address is not wrong, but it is a small incoherence someone could notice.
• Follow the obligation. Where a customer or a regulator requires data to remain in a particular country, that decides it outright.
• Spread the remainder. For sites with no strong tie either way, distribute rather than clustering. There is no cost to doing so.

What country selection does not change

It is worth being precise, because this is easy to over-read. Choosing a country changes where the address is announced and where the data sits. It does not change the language of your site, the domain you registered, the registrar you used or anything else about how the property presents itself.

An estate of nine sites in nine countries that all run the same theme, were registered on the same afternoon, and link to each other in the same pattern has not gained much. Country selection is one more axis, not a substitute for the rest.

Mixing with the American pool

Both regions can sit on one billing account and one control panel, so an estate can hold European and American addresses simultaneously without any administrative separation. That is a wider spread again, and it is the natural arrangement when the audience genuinely spans both.

Data residency deserves one caution: if part of your estate is under an obligation to stay inside a particular area, keep that part clearly separated in your own records so that a later reassignment does not accidentally move it. The reassignment tooling will happily move a site anywhere you hold an address, and it does not know about your obligations.

The regional pools and their sizes are described on SEO hosting in Europe and the American page. Reassignment between addresses is covered in IP Diversity.