The latest SDK supports both BCM4343W and BCM43438 as platforms as you know.
So if your supplier provides 43438 based module, you can use it I think.
Of course BCM4343W can be used instead of BCM43438(WLAN+Bluetooth).
By the way, only fewer people check messages in this group,
so I recommend to post your question to WICED Studio Wi-Fi/Combo Forums (not to Homekit group).
I moved this to the WICED Wi-Fi forums.
The BCM4343W and BCM43438 are packaging options for the same chip.
The BCM43438 is an SoC based design, so it is not supported here on the community and there is not an associated dev kit.
Which STM32 is your hardware vendor recommending? Most STM32 don't have enough SRAM to run homekit.
Thank you very much for moving and confirming the difference.