Sounds like you will need a custom made bot:
-Scrape newest questions (quora, yahoo,...)
-Filter scraped questions by keywords
-Chose a answer (from templates) manually
-Post answer thru api or browser automation
Shouldn’t be too expensive but I don‘t know the actual rates of the botmakers here. Mostly reusable components as most developers got ready to use components for scraping sites or browserautomation.