You can probably guess that most MG releases are niche products that don't sell well, but I don't know if people are aware of exactly how poorly they sell. Most releases on the MG store sell well under a thousand copies, and it's extremely rare that something goes over 2000. The Alicesoft games generally sold 1500-ish on the MG store, though Sengoku is close to 2000 last I heard. Evenicle has sold closer to 15000 total thanks to being on Steam, although Steam takes some of that profit, and most games don't do that well on Steam either.
Translation is the main service that MG provides, so the rates for translators are actually better than most other roles. Editors seem to make half a cent per character for the most part. 'Project managers' make a flat fee of at most $100 for a project that may go on for years, so there are no dedicated project managers, just people in other roles who take that position as well. Testers previously made a flat fee of $50 a project and got a free copy of the game, but I'm told that just recently they may make up to $200.
The maximum rate for a translator at MG is currently 1.75 cents per character, a raise from the previous max rate of 1.5 per character back in 2016, as I recall. What many would consider a normal, comfortable rate for more ordinary fiction translation jobs is 4000 characters a day, at which rate you would be making $70 a day and something like $17000 a year if you dared to take vacations.
TL;DR: Mangagamer apparently underpays translators and everyone else.
That seems to be quite normal though in the space of visual novel publishers. Heard it from other people working for other VN companies, that they pay you pennies.
I wonder what can be done about that though? The visual novel market, thanks to Steam, exploded. A decade ago you had maybe 3-4 prominent visual novel releases each year. Now you have like maybe 100, with Indie VN from everywhere. Taiwan, Korea, Japan, China, self-published, published etc.