NB! It seems this console command is not compatible with CS2.
Command Profile

M_MOUSEACCEL2

CS:GO

This console command sets the mouse acceleration value for its second threshold, up to 4x movement speed.

Syntax
m_mouseaccel2 [Value]

Description

This console command sets the mouse acceleration value for its second threshold, up to 4x movement speed.

Syntax And Arguments

m_mouseaccel2 [Value]
Value The value you want to set mouse acceleration to for the second speed threshold (up to 4x). The default value for this command is 0.