I've put Enoli Paredes and William Contreras on debut waivers. Andres Gimenez is already on waivers.
Here is a summary of how this works. This ESPN page shows all MLB debuts: http://www.espn.com/mlb/debuts. It shows roster debuts which is good; a player does not need to pitch or get an AB to show up on the list, they just need to have been on the active roster.
Our rule states that players can be added freely "as soon as 8 PM Eastern Time on the day following their first day the real life 26-man MLB roster." If you want to add a player who was recently called up, you can check the ESPN page to make sure their first day on the roster meets the requirements.
The vast majority of players will not go through waivers as the majority will not be worth claiming in our league. I will try to check the ESPN debut site daily and if I see any actual prospects I will slap them on a 2 day waiver period so the league has a fair shot at them. Who I slap on waivers will be completely arbitrary and I might miss some guys who are good if I don't know about them. I'll ask other commissioners to check the ESPN site too as I won't be able to every day.
If a player is promoted and anybody in our league wants them to hit waivers, just post about it and we will add them. If anyone worth claiming is promoted just bring them to our attention.
To put someone on waivers you go to Commissioner > All Options > Player Status Override