Here’s your answer, at least in theory:

https://united24media.com/latest-news/russia-allegedly-plans-to-assign-one-interpreter-for-every-30-north-korean-soldiers-ukrainian-intelligence-reports-3295

I’m guessing that they’re gonna either try to have NK forces operate together, or gonna put them in roles that involve minimal interaction with other forces.

I expect that it’s some degree of problem, no matter what.

One element that’s kinda important in US military theory is the idea of the OODA loop.

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

The OODA loop (observe, orient, decide, act) is a decision-making model developed by United States Air Force Colonel John Boyd. He applied the concept to the combat operations process, often at the operational level during military campaigns. It is often applied to understand commercial operations and learning processes. The approach explains how agility can overcome raw power in dealing with human opponents.

https://www.google.com/search?q=%2Booda+site%3Amil

The basic idea is that the smaller that loop is, the more-quickly you can react to your opponent while they’re still trying to react to your prior actions, the greater the advantage. In some cases – think the Battle of France, where at a high level France had slow response time – it can lead to staggering differences in outcome.

Language barriers exacerbate that sort of thing.

In US military history, I remember that that was blamed for a lot of problems surrounding the Battle of the Java Sea, a serious Allied naval loss.

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

The Allies had a scratch force of American, British, Dutch, and Australian ships.

Unfortunately, these didn’t use common cryptographic mechanisms to encode communications, and the operational command was with the Dutch, who at the time didn’t work in English.

As a result, you had stuff like American reconaissance planes who would encode and transmit encoded data in English to a ship, which would decode the information, which would – assuming no extra relays were involved, which would involve more decoding and encoding – hand off the information in plaintext to a translator who knew English and Dutch, who would relay the Dutch to the person in command, who would make a decision on response, which would hand that back off to a translator, who would translate that to English, and encode and send the orders to, say, a British ship, who would decode those and relay to the ship commander, who would order people to then do something.

One of the things NATO did was establish common communication hardware and standardize on a subset of English for operational stuff to cut into the length of that loop.

I read somewhere a few days ago that there’s supposed to be something like one translator per 30 (?) North Koreans. I don’t know if it’s accurate.

Honestly I’m a little surprised they don’t make them learn at least some Mandarin or Russian as soldiers, or maybe they do but at higher ranks?