It's a bit more involved:
in LE10 you need to change CONFIG_SND_SOC_TLV320AIC3X in projects/RPi/devices/RPi4/linux/linux.aarch64.conf to 'm', in LE10 you need to set CONFIG_SND_SOC_TLV320AIC3X_I2C to m
But the soundcard also needs a soundcard driver (dacberry400.ko) in addition to the device tree overlay.
The source code for the driver is in the src directory, but as the provided Makefile is a bit of a mess you'd need to adapt it before you can add a separate driver package for it to LE and include it in the LE build (see packages/linux-drivers/ for various out-of-tree driver packages).
Certainly doable, but a bit of a PITA.
As you payed good money to the manufacturer I'd prod him a bit more to get the sound card driver included in the official RPi kernel - or try to get a refund and buy a card with better support.
so long,
Hias