1. Yeah you can flash dracula or kermit kernel then flash magisk if you want magisk hide to work without gplay services crashing.
2. Updating lineageos will overwrite your current kernel with the default one that can cause GPservices crashing, but you can always flash other kernels on top of it.
Keep in mind that everytime you want to switch between kernels that uses anykernel2 (dracula and kermit for example), you have to flash your rom's boot.img found in the rom.zip... flash boot.img through TWRP then flash the kernel.zip that you want, then flash magisk/supersu. To revert back to stock kernel, just flash the boot.img then flash root if you want root access.
after this I've after 5 days waste of time a ROM which works (but with another kernel and firmware from STOCK because of no camera with LOS FW)
I hope, this will be fixed in the future, too.