Redesigning MOSFET switches
You can replace it with an MOS transistors. No problem.
The BJT had an internal resistive divider to increase the threshold where the switch &quot;flips&quot;. I am wondering why was it implemented inside the BJT. The transistor is less versatile this way. But I also not see any reason why a BJT should be used here. The current it has to supply is very low, in the 10uA range. An MOS transistor in general is a better switch. The only critical point might be the higher sensitivity of an MOS gate to an ESD event. If the control signal comes from a switch (i.e. not from an electronic circuit) you might consider adding some ESD protection. The base terminal of a BJT is basically a diode, which protects itself for every cases, but the most extreme ones.