Issue with booting Manjaro from encrypted NVMe drive on pbp

[Cs137]

I am trying to operating a pbp with a system booted from an encrypted NVMe drive, but I stuck at the same step and would appreciate any help:

•  I use an unencrypted partition on the eMMC acting as boot partition that holds the kernel and an initramfs. The latter was build taking among others the hooks `plymouth`, `plymouth-encrypt` and `lvm2` into account.
  
• I am trying to boot a Manjaro (22.12) system which is located on a btrfs filesystem within the encrypted container on the NVMe.
  
• As bootloader I use Two-Boot (on 1st partition of eMMC), which works and allows me to interrupt the foreseen boot process in order to boot from SD. If I do not interrupt it and try to boot via eMMC from the NVMe, the image file is provided (which is the only thing I get since a dialogue is shown just very shortly). Then it stucks with a black screen and a green power led.
  

I append the following options via the `extlinux.conf` file:

Code:

cryptdevice=UUID=<ID-OF-NVME-DEV>:<LABEL-AS-APPEARS-IN-MAPPER>:allow-discards root=/mnt/mapper/<LABEL-AS-APPEARS-IN-MAPPER>/ rootflags=subvol=@ rw rootwait audit=0 plymouth.ignore-serial-consoles

The ID, label and subvolume I use is the correct one, but I have to admit that I am unexperienced so far regarding btrfs.

The fact that I am not prompted for the passphrase indicates me that the hook is either not implemented correctly in the initramfs, or not called correctly.`mkinitcpio` did not show an irregular behaviour during the creation of the initramfs (build via chroot from within the system I try to boot). In another approach I tried the `enrcypt` hook instead of `plymouth-encrypt` which did also not succeed. Moreover, I read here that one should use`plymouth-encrypt` if plymouth is in use, which is the case for Manjaro.

Something that I recognised is that the initramfs is not build using the kernel sources of the system:

Code:

mkinitcpio -p linux
==> Building image from preset: /etc/mkinitcpio.d/linux.preset: 'default'
  -> -k 6.0.12-1-MANJARO-ARM -c /etc/mkinitcpio.conf -g /boot/initramfs-linux.img
...

Code:

cat proc/version
Linux version 6.1.2-1-MANJARO-ARM ...

I would be happy for any hint that might be helpful to solve my issue.