I have just saved three render settings in S26.
Here I used the default suggestion, and with that, they are stored in the Asset Browser.
Loading them showed me a “123abc” sorting. To test that, I renamed those several times in the Asset Browser. Each time the sorting was updated accordingly.
To remove the unused settings, please go to the folder where they are stored and delete those.
Since I can’t reproduce here the non-123abc order, please get in touch with the support.
All the best