Use wpad-mesh-wolfssl since the wolfssl library is already in the ROM.
Wolfssl has been frequently updated so you'll need to start with a new ROM having the updated wolfssl and the packages that it uses. Otherwise installing wpad will try to load the new wolfssl while the other one is still there, and it will run out of space.
The cram-down can be done with attendedsysupgrade or the image server.
While that is 'a' plan (not 'the' plan, yet), it hasn't happened, yet (not in master, only wpad-mbedtls packages have landed there so far) - so wolfssl is still the way to go (unless you really know what you're doing and/or building from source).