What about Question Answer?

From plugins repositorry

Description DescriptionBuilt Question Answer site for your WordPress.Question Answer by www.pickplugins.com

• Question Answer – Bundle
• Live Demo
• Documentation

Plugin Features

• schema.org support.
• Archive page via shortcode.
• Frontend question submission form via shortcode.
• Awesome account page via shortcode.
• Ton of filter & action hook to extend.

Archive page features

• Responsive archive page for questions.
• Featured question at top with highlighted background.
• Question solved marker.
• Search & filtering by user slug, category, keywords, question status.
• Search by question categories.
• Different sorting by title, comment count, latest & date.
• Display view count for questions.
• Display answers count.
• Display up vote & down vote buttons.
• Breadcrumb navigation & menu.
• Add question button at top right.
• User thumbnail.
• Pagination.

Single question page features

• Breadcrumb navigation & menu.
• Admin can change post status.
• User thumbnail, role display.
• Question category, posting date & time, total answer count display.
• Admin and quesiton poster can make the question as solved or un-solved.
• Any user can subscribe the question to gey notifications.
• Admin can marked as featured question.
• Question comments.
• Subscriber total count & list with thumbnail display.
• WP Editor for answer posting.
• Private or public answer. private answer only can display admin and question poster and answer poster.
• Answer sortings by voted, top voted & older.
• Best answer, admin & question poster can choose best answer. best answer can be remove future and choose another.
• Answer up vote & down vote.
• Answer comments. ajax based submission.
• Flag for comments to warn user.

Question submission for features

• Based on filter hook & easy to extend for add custom input fields.
• Default input fields are title, content, status, categories, tags.
• reCAPTCHA on question submission.