We have two sites/blog, and now we are merging the two blogs into one blog. We move content from domain2.com to domain1.com. What should I consider when it comes to SEO. Should I move all the traffic from domain2.com to domain1.com? And then 301 redirect articles from domain2.com to matching the imported articles at domain1.com?
You should merge similar posts one by one before setting-up 301 redirection and try to maintain quality and You can do 301 post-wise.
Do not merge irrelevant post or don't redirect irrelevant post.
You can also beef-up thin content to maintain quality.
If you are deleting posts then show 404 error.