I’ve been flying Arducopter in my TRex 500 fbl heli for some time now in Stabilise and AltHld modes but would like to be able to be able to configure it to behave more like a flybarred heli with a heading-hold tail gyro. Browsing the flight modes it seems to me that AcroTrainer parameter 1 might be the appropriate mode, but the wiki doesn’t say if or how it controls the tail.
The acro mode does provide a virtual flybar feature. This has nothing to do with the tail. The tail will behave similar to that of stabilize mode but you can change the feel of it to be different with the max rate and time constant.