Yes, the ATR is also fitted with AC generators, dubbed "AC wild" for wild frequency, i.e. unregulated.
In cruise, the AC frequency is at or close to 400Hz anyway, but the AC is only used to supply power hungry equipment that does not need stable 400Hz, like ice protection, windshield, pitot, hydraulic pumps, etc. Therefore it does not require the additional (and heavy) IDG/CSD whatever, as no specific frequency is vital to make the said equipment work.