Thanks Mohamed_Ahmed_Kansoh. (Somehow I didn't see this suggestion until just today - my apologies)
Localization overall is in the back of our minds. This would probably help with some things (buttons and other interface items) but generally speaking, in the editor, we tend not to try to be over-prescriptive about how a member writes. Just like a verbal conversation, with stutters, uhhs', and clarifications our forum is designed to be accepting of styles**.
THAT SAID - being clear is pretty critical. Since our toolsets are web-based I think users who are more concerned about spelling and accuracy tend to invoke browser plugins which work quite well for spell-checking etc.
One other thing - there are changes coming to the interface in the next several months that may include such tools (or at least enable us to add such tools easier than we can now) but that is coming out of the platform vendor and I don't have clear visibility *yet* about how much / how fast that may arrive.
If you have examples or more ideas please add them here - I'll set this to Needs Info in case you (or anyone else has something to contribute).
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** For that matter - this is just an idea - with the proliferation of translation tools I even welcome writing an answer in your native language and then copy/pasting out of something like Google Translate and including them BOTH in your answer.