I’ve seen the following usecases for eMode on stables.
1.) Shorting/longing the Euro.
Some markets (polygon) offer stable-eMode for both EURO and USD denominated stablecoins. This was a popular way to bet against the falling EURO in H2 2022.
2.) Shorting USDT
Or more generally, people use eMode to short stables which, they view, are more likely to depeg (to the downside).
3.) Arbitrage (as mentioned earlier)
If we were to turn stablecoin eMode into ‘USDC eMode’ (DAI, FRAX, USDC) we would remove usecase 1 and parts of 2 and 3.