Activate Acro Mode with Betaflight/radio?

Hello! I have a 3" race quad that came in a kit with a Jumper T-Pro and goggles. The copter was already configured and ready to fly and flies great. The RC link is FrSky. 20A ESC and F405 FC.

Using the right toggle switch on the radio, I can switch from position 1: Angle Mode to positions 2+3 (it feels like there is no difference between the two): "Acro" mode while flying. However, the quad is never in full Acro mode. The gyro always tries to stabilize the copter as soon as the sticks go to zero and no input is received. The annoying thing about this is that if I try to fly a bit freestyle and, for example, want to switch from a dive to a loop during a maneuver and the sticks are briefly in the neutral position, the quad stabilizes immediately. So my question is: How can I activate full Acro mode? And: is it possible, and if so, how – via the radio or Betaflight? I'm new to the hobby and have more than limited knowledge of either OpenTX on the Jumper or Betaflight.