mo is Moldavian, not Romanian (which is ro).

Where and in which language do you see this choice ?

Moldavian have same language romanian because not exist other just one romanian.

https://en.wikipedia.org/wiki/Moldovan_language

You have a point. But we use language-country pairs of ISO 639-1 - ISO 3166-2 codes, so all content made in Romanian (Moldovan) language in Moldova should be added as ro-MD (we should also use MD instead of MO for Moldova as per ISO 3166-2), which I suppose doesn't help you much. But I'll report it to admins, maybe they'll find a time to correct both codes.

Perhaps it is better to reverse the positions.
Instead of writing Romanian (Moldovan)
write Moldovan (Romanian)
That way it will be in another position in the dropdown list.

This was not corrected.

There is no Moldovan language and it never existed, it was an invention of the Soviet Union. In March 2023, the Romanian language became the official language of Moldova, replacing the Moldovan language in all laws of the Republic of Moldova, including the Constitution. From October 2023, the Romanian language was decreed the official language for approximately 1 million Romanians in Ukraine, thus replacing the Moldovan language. The Wikipedia article about the Moldovan language has been proposed for deletion.

When I try to add a description to a movie or a series in Romanian to the Moldovan language section, the website sends me to Google Translate. There is no Moldovan language on Google Translate.

https://imgur.com/mSFfc8U

To select the Romanian language for a newly added image, "Română" appears twice.

https://imgur.com/E7QLDrZ

• Română - the Moldovan language can be deleted
• Română - the Romanian language