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Using one shared reset signal across two rigid boards connected by flex PCB — good practice or risky?

I am working on a rigid-flex design with two ICs placed on different rigid sections:

an [MCU](https://www.st.com/resource/en/datasheet/stm32wba5mmg.pdf) on one board an [AD5941](https://www.analog.com/media/en/technical-documentation/data-sheets/ad5940-5941.pdf) on another board

The two rigid sections are connected by a flex PCB. This is a 4 layer board. This is the[ stack-up](https://www.we-online.com/files/pdf1/en_flex4_4f_023_12_2v13.pdf).

![Image_alt_text](https://electrical.codidact.com/uploads/2qun6m98whw1vrsdz5qau0fe5vx2)

I am considering using **one shared system reset signal for both devices**, so that pressing one reset button resets both the MCU and the AD5941 at the same time. This reset net would run from one rigid section to the other through the flex.

The other signals routed in the flex section are,

SPI
TWO LDO ouputs(3.3V)
GPIO lines for enabling the MUX

I would like to know whether this ( RESET) is generally considered okay in practice, or whether it may create reliability issues.

**RESET CIRCUIT:**

![Image_alt_text](https://electrical.codidact.com/uploads/cxxqikz7biq5umnc6857yi2xzf73)

**My doubts are mainly:**


 1. Can a reset trace routed through the flex pick up noise and cause false resets?


 1. Since the reset line is longer than a local reset trace, do I need any special protection or filtering?


 1. Is it better to keep a common reset for both ICs, or should each device have its own separate reset?


 1. If a shared reset is acceptable, what layout precautions are recommended?

     keep away from clocks/SPI lines?

     route with solid return reference?

     add series resistor?

     RC close to source or destination?