The Sample Size Determination with Latent-State-Trait Models

As part of a research project at my university i have to determine the needed sample size within a latent state trait model.
I am searching for a rule of thumb for LST models and what is recommended from simulation studies. Unfortunately i can´t find very good input.
Beyond that i´m asking myself, if someone knows a Shiny App that can be used in such manner.

Maybe somebody can help :slight_smile: