In my opinion there must be possibility to simulate projects from WinnCC Unified Online. Doing changes/debugging without simulator is ridiculous.
The best idea would be if projects from TIA will be compatible with WinCC Unified projects then simulator is ready.
Second option is to create simulator option in WinCC Unified Runtime.
Is it possible to introduce?
To my Knowledge it will not come before Quarter2 2024
Do you know when?
the Engineering will be done via TIA Portal in future, so you can use the TIA build in Simulation to simulate your projects.
I hope this helps