Odoo supports multilingual on two levels: interface translation (menus, buttons, labels) and content translation (product names, web pages, email templates). Both are handled but in different ways.
Install languages
Under Settings → Translations → Languages → Add a language. Swedish (sv_SE) and English (en_US) are most common. Odoo downloads translation files for installed modules. Quality varies: standard modules are well translated, community modules may have gaps.
Interface translation
Menus, field labels, buttons, and error messages. Managed via .po files (standard gettext format). Import and export under Settings → Translations. Missing a translation? Edit directly in Odoo (Settings → Translations → Translated Terms) or in the .po file.
Content translation
Product names, descriptions, web pages, and email templates. Odoo 18 stores these as JSONB with language keys: {"en_US": "Product name", "sv_SE": "Produktnamn"}. Switch language in the interface, edit the field, it saves per language.
Website
Odoo Website supports multilingual pages. Each page can have a Swedish and an English version. Language switcher in the header toggles between them. URL structure: /sv/page and /en/page. SEO metadata (meta title, description) is set per language.
Common problems
Incomplete translations: a field shows in English in the middle of a Swedish interface. Debug via the Translated Terms view. Translations overwritten during module upgrade: export your custom translations and import after upgrade.
For a company with Swedish and English as working languages, Odoo's multilingual support works well. For ten languages with complex content structure, more planning and a dedicated translation process is needed.