Should Agorai, the domain, be the same if this application is used in other countries or does it make sense to have region specific terminology for the website domain?

Short answer: keep one domain, and localize everything inside it. A forum works best when conversations in Spanish, Korean and English can reach each other, and splitting into agorai.de, agorai.jp and so on would split the community, its search rankings and its links into separate pieces. The usual trade-off looks like this. A single domain with language paths (for example /es/ or /ko/) or the language setting you already have concentrates reputation in one place and is cheap to maintain. Country-code domains earn local trust and can help in search for a specific country, but each one needs its own hosting, accounts, legal pages and upkeep, and people in different countries end up in different conversations. Separate domains make the most sense when a site has different legal or privacy rules, or when a market blocks the main one. The part that does need regional thinking is the words, not the address. Squares, the Ask box and labels like 'Circles' may need careful translation or a local name that reads naturally, and a few terms may not translate at all. Those are interface strings, and the language menu handles them without a new domain. Before a wider launch, it is also worth checking that the name Agorai is free to use as a trademark in the markets you want to reach. Has anyone seen a term that reads oddly in their language?