Can an SEO company handle international campaigns?
Yes, if it runs each market as a campaign of its own inside one program: its own keyword research, content, links, and targets, coordinated so that the markets share a strategy and a reporting format. The technical setup of an international site, such as the URL structure and the tags that tell Google which page serves which language or country, is the foundation, but it is not the campaign. Before hiring, find out how the company chooses and sequences markets, who does the work in each one, and how it reports market by market.
Choosing markets and their order
Adding a market adds research, content, outreach, and management time, so the order matters. A sensible case for each market rests on evidence that people there already look for what you offer, on your ability to serve them (delivery, support in their language, local legal requirements), and on the competition in their search results. Starting with one or two priority markets lets the company prove its process before the program grows. Ask the company to show you this reasoning for each market it proposes.
Research and content for each market
Each market needs keyword research done in that market, with tools set to its country and language and, ideally, checked by people who search there. A translated keyword list misses the terms local searchers use, and the same goes for content: wording, examples, prices, units, and buying steps have to fit the market. Translation tools can help with drafts, but there is a line Google draws. Its spam policies list, as an example of scaled content abuse, “Scraping feeds, search results, or other content to generate many pages (including through automated transformations like synonymizing, translating, or other obfuscation techniques), where little value is provided to users”. That example concerns content taken from elsewhere, but its test, many pages with little value for users, is the right one to apply to your own translated pages: bulk machine translation that nobody adapts or checks adds little.
What Google may already show in other languages
In some languages, Google may already be putting your content in front of searchers without a localized version. Its documentation on translated results explains that Google sometimes translates the title link and snippet of a result that is not in the language of the query, for a listed set of languages, and that a searcher who clicks is shown a machine-translated page with the option to view the original. Clicks and impressions from these results can be checked with the Search Appearance filter in Search Console’s Performance report, and a site can opt out with the notranslate rule. For a campaign, this is evidence: impressions through translated results in a language suggest demand there, and the quality of the machine translation shows what a properly localized page would need to improve on.
People in each market
A company needs people who know each market it works in. Some companies employ specialists for major languages; others coordinate local contractors or partner agencies. Either can work. What you need is a clear answer on who does keyword research, writes or reviews content, and handles outreach in each country, and how their work is checked. Link building is a local job too: sites that carry weight with readers in one country may mean nothing in another.
Reporting market by market
A combined traffic figure can hide a market that is failing behind one that is doing well. Reports should break out organic traffic, rankings, and conversions for each market, set up in your analytics so you can see them yourself. That view also tells you where to add budget, where to hold, and whether a market should be paused before more money goes into it.