It seems that I got some new Information.
root@Storage:~# btrfs check --readonly /dev/nvme1n1p1
Opening filesystem to check...
Checking filesystem on /dev/nvme1n1p1
UUID: 42e113ba-7b36-4254-9cc5-289204f277d7
[1/7] checking root items
[2/7] checking extents
Chunk[256, 228, 3232018464768] stripe[1, 18446612686497164688] is not found in dev extent
Device extent[1, 182558130176, 1073741824] didn't find the relative chunk.
[3/7] checking free space tree
[4/7] checking fs roots
[5/7] checking only csums items (without verifying data)
[6/7] checking root refs
[7/7] checking quota groups skipped (not enabled on this FS)
found 234483277824 bytes used, no error found
total csum bytes: 203991872
total tree bytes: 1362182144
total fs tree bytes: 981958656
total extent tree bytes: 142671872
btree space waste bytes: 222324441
file data blocks allocated: 567919054848
referenced 225167265792
root@Storage:~# btrfs check --readonly /dev/nvme0n1p1
Opening filesystem to check...
Checking filesystem on /dev/nvme0n1p1
UUID: 42e113ba-7b36-4254-9cc5-289204f277d7
[1/7] checking root items
[2/7] checking extents
Chunk[256, 228, 3232018464768] stripe[1, 18446612686497164688] is not found in dev extent
Device extent[1, 182558130176, 1073741824] didn't find the relative chunk.
[3/7] checking free space tree
[4/7] checking fs roots
[5/7] checking only csums items (without verifying data)
[6/7] checking root refs
[7/7] checking quota groups skipped (not enabled on this FS)
found 234483277824 bytes used, no error found
total csum bytes: 203991872
total tree bytes: 1362182144
total fs tree bytes: 981958656
total extent tree bytes: 142671872
btree space waste bytes: 222324441
file data blocks allocated: 567919054848
referenced 225167265792
On both drives it now shows a missing chunk