I had an idea for a game. Unfortunately not one that could be easily played over the internet, except possibly video call, but tell me what you think of it.
The base concept is that it's about communicating something, without speaking or writing something down. Any use of Sign language is highly encouraged, in fact one of the ideas I had for this was "it'll incentivize learning Sign vocabulary", but if everyone's fluent in the same Sign language then it would trivialize the thing.
It starts off with a reason why you can't verbally speak to each other -- like a grumpy person is sleeping, or a very loud environment, or auditory sensors you don't want to trip, or everyone has bronchitis -- and why you can't write anything down (assumed by default to be that nobody has paper and a pen or pencil). Also, there's the general type of situation you're in; are you trying to escape from somewhere, find and retrieve an object, scout out a location, etc. This can be discussed as a group, or generated randomly, but it all takes place while you're allowed to talk; this is the stuff everyone knows going into the thing.
There's a bunch of word tiles, or actually it would work better (easier to produce, easier to carry) for them to be on cards, but I first thought of it as "tiles" so that's what I'm going to call them. They each have a word on them; and ideally, also instructions for how to say that word in the local Sign language. During the game, the only words you're allowed to speak (or write) are word tiles that have already been played. So, if word tiles for "cape", "box", "red", and "salt" (which are just the first words I thought of, not necessarily what should actually be in the game) have been played, you could say "red box red salt" (the red container has cinnamon in it?), or "box box cape" (there's boxes of capes? there's a cape next to the boxes?), or "salt cape" (…okay I can't even think of what that might mean). Even if you're verbally saying those words as a player, in-game you're considered to not be speaking out loud; maybe the word tiles represent Sign words everyone already knows, or large words on a nearby poster, or any other explanation left as an exercise to the reader.
The game starts with X number of randomly-drawn word tiles already played, and Y number of random word times given to each player. Before the first round of discussion, everyone picks one of their word tiles to play, which increases the group's total vocabulary from X to X + (number of players).
Before play begins (right before the stuff in the previous paragraph, but after it's been established the basics of what you're trying to do), everyone gets randomly-selected information they need to convey to the others. It can be adapted to better fit the theme; in which case, write down your altered information, because that's what any guesses will be compared to. A game is fully successful if by the end of it, everyone has correctly received the information from everyone else. Considering what you need to get across, you can choose which of your word tiles to first play, to expand the group's vocabulary in a direction you think would be useful.
Once the group's "starting vocabulary" has been established, then comes the first round of discussion. You can use gestures, facial expression, any Sign you might know, to try and get across your information, and learn everyone else's information; but the only spoken or written words you can use, are from word tiles that have been played. The round ends once everyone agrees they've learned all they can at the moment; that they've either figured it out (unlikely after a single round, but possible), or they've hit the limits of their collective pantomime skills with the given vocabulary. If the game continues to another round, then everyone picks another word tile to play, the group's vocabulary expands by the number of people in the group, and another discussion phase begins.
There's a hard limit on how many discussion phases you can have, and that's "how many word tiles do people have available to play". Aside from that, and the ever-present but rarely-mentioned "people are starting to get tired of playing", end conditions might be a time limit, or a set number of rounds; of course, "everyone believes that they know the information which everyone else was trying to convey" is the "completion" condition. I also had the idea, that some "this is the information you need to get across to the others" cards might have a "rounds limit" on them, the concept being "this is something time-sensitive, which people need to know about as soon as possible or else there will be Problems", although that necessitates a mechanic for "everyone guesses the thing ONE person was trying to convey", allowing for partial victory partway through the game.
When it comes to "using the vocabulary the group has access to", it might work if each word tile is actually a rubber stamp, so nobody is physically writing or verbally talking. The problem is an that would require making stamps, and having a stamp pad available so "using a stamp" is feasible; plus I've almost never seen that kind of thing since I was a child, so I don't know how common or cheap/ expensive it is these days. (I mean I didn't know how much it cost when I was a child because, you know, child, plus that was a good deal of inflation ago so the price wouldn't still be accurate even if I remembered what it had been.) The up-side to this idea though is that rubber stamps are cool.
If everyone feels that they know what information everyone else was trying to convey, they write it down; then everything gets revealed, starting with the guesses for one person's information, then what that information actually was. "Completely accurate" is easy to tell, and "close enough" is interpreted on a case-by-case basis. If more than half the players get it right (or close enough), it counts as an "eventual success", under the assumption that the people who got it right can correct the people who got it wrong. If less than half get it right, then the narrative consequences are whatever would happen from failing to understand that particular piece of information, which might be "missing a shortcut so the trip takes five minutes longer", or "getting attacked by a coyote".