I am running a successful informational website on one specific topic (branded domain name) in German language on a .de domain.
Now 2 years ago I started an international website on that topic with German, English, Russian in sub-folders. Also a branded domain name (another, shorter brand) on a .com domain. Focusing on a more specific sub topic of the topic.
Now I plan on working on the international website making it bigger, broader in topic, not focusing on the sub topic any longer.
What would you guys suggest?
a) redirect the German content of the .com to the already successful .de domain and just doing the other languages on .com?
b) redirecting the .de domain to the .com and let all languages benefit from each other in SEO power?
Of course either scenario would be equipped with hreflang. My first thoughts were b) with a lot of fear of losing rankings. Then I thought a) is probably the most clever solution. Any further ideas or thoughts? Thanks in advance for your brain power :-)