hello, i don't know for your model, but on osp300 there is a parameter that allows controlling acceleration for manual_mode, automatic_mode_normal_cinematic and automatic_mode_hi-g_cinematic
even so, editing those parameters is a bit restricted by CE regulations
i don't know if those parameters are available on your control ?!
also, so far, i have not seen g-codes that allow changing the acceleration ( from code )
i know that our okuma dealer had edited those acceleration parameters, by messing with some internal values inside the controller, thus using a procedure that is not available to mere mortals maybe there is a chance that such a procedure can be executed also on your cnc; try talking with your okuma dealer about it / kindly