Hello,
Hope you have seen this document for how to integrate it will QnA maker. https://learn.microsoft.com/en-us/azure/cognitive-services/luis/luis-tutorial-bing-spellcheck
Then You can do this with Dispatch Bot. When you get the results back from the recognizer, there will be an alteredText value if spell check made a correction. What you're wanting to do is replace the original text with this new value.
const recognizerResult = await this.dispatchRecognizer.recognize(context);
if (recognizerResult.alteredText) {
context.activity.text = recognizerResult.alteredText;
}
<code to select intent>
var processResult = await this.qnaDialog.processAsync(userDialog.qnaState, context.activity)
QnA Maker should now receive the query with the altered text. Try to modify context.activity.text and removed or @ mentions from Teams, which were affecting intent identification and QnA answers.
Regards,
Yutong