From what I’ve read, the multisite feature is used to create a multilingual website. How tightly are the sites isolated from each other? For this to make sense, both sites should be able to use the same theme. This probably won’t work because the pages are localized. This might also apply to the layout.
How do you create bilingual websites without using any automatic translation plugin?
first of, I would ask myself if the website is purely informative or does it use specific data models ?
If so, does this data model need to be translated or not ? example: an e-commerce product.
A multilingual site is characterized by the fact that all text and navigation entries are displayed in the desired language. In other words, everything you see.
The layout, markup, and CSS are language-independent.
Naturally, the “pages” must be maintained in duplicate. The editor must be able to enter the texts in, for example, German and English.