I do have a case where exist 3 shops with 3 different languages and 3 subdomains. For example, (1) spanish.myshop.com, (2) english.myshop.com, (3) german.myshop.com.
An argument to merge all 3 shops to 1 is for more effective shop management.
However, my concern if I merge 3 shops into 1 and implement a language app like Weglot, I won't be able to differentiate communication between the markets. For example, using effectively Bold upsell or cart abandonment apps depending on the language.
I might be wrong, so please if you have experience share your point.