See if you can locate a copy of Grant Haist's Monobath Manual.

One of the problems with monobaths is that they must be fine-tuned for each particular film. For example, a monobath created for Plus-X need not work well with Tri-X. This in part negates their usefullness.

Another problem is that the rated film speed for a film is usually not the same when developed in a monobath as opposed to a conventional developer. Plus-X could be faster than Tri-X.

Most of the useful monobaths use hard to obtain and possibly dangerous ingredients.