I will share here a list I put together on Duolingo course vocabulary lists here on Memrise. Where multiple courses exist, I try to prioritize the ones that are (1) actively maintained, (2) most complete, and (3) most used. This list was also posted on Reddit.
Hungarian (no course yet) Hebrew (incomplete) Greek (incomplete) Czech (incomplete) Romanian (incomplete)
Swahili (no course yet)
Hindi (no course yet)
Klingon (no course yet)
Korean (no course yet)
Indonesian (no course yet)
Someone started posting the reverse course, though it appears they stopped before getting too far. I focused only on trees that are “X for EN speakers” and mostly complete so I left that one out.
As for the Latin one, that is definitely interesting though I plan to stick with the existing Duolingo courses for this particular list. Hopefully Duolingo adds Latin.
A few days ago I have noticed that on the Swedish Duolingo course, on audio questions the sound won’t start automatically. That passed!
Today on the translation-audio questions the right answer got stuck. I had to press a few times to make it sound. It happened almost on every occasion.
I thought the mechanism of Memrize is universal. How can these problems occur only on few? Or one? Or whatever!
I completed entry of vocabulary in the Vietnamese course, now filling in audio.
I added a section of “Duolingo inspired” courses; I only found two that seemed worth mentioning at the moment. There are others, though most are either incomplete or disorganized.