I asked MusicLabs if they don't want to develop a Bass vst with their engine. The MusicLabs guys told me that they will release a bass vst called RealBass in 2025 that they are currently working on. This should finally be a bass with a very good key switching system. I'm currently using Ample Bass, but the bad key switching system annoys me every day.
Anyone who is still looking for a well-playable bass guitar, just like me, could wait a moment...
Patrick