The Z8000 series (Z8300, Z8500 and Z8700) has dedicated hardware support for H.265(HEVC) decoding, the z3735f does not.
Since videos can be encoded in many different ways you’d probably be able to find a HEVC video that will choke any device built around the above SoCs, but for practical purposes I think you could get away with the Z8300.
If you’re looking at a battery powered system I’d be wary of battery capacity though 😉
Oh, and also make sure that the manufacturer hasn’t reduced the performance of chip to extend battery life, for example the Teclast X98 Plus might be unsuitable for your requirements.