zpool stripe degraded due to wrong vdev

[Beeblebrox]

Hello.
I was experimenting with Zfs-on Linux and I now have a corrupted zpool. My mirrored pool is ok, but the striped mirror shows a) removed vdev partition from the stripe and b) added ext4 vdev (where Linux root is) to the stripe. The pool is currently in an exported state, has no external zil/cache.

I know the ZDB options, but I though it best to ask before I went ahead with any operations on the pool.
1. I need to "zpool detach" the ext4 partition and "zpool add" the original partition to the stripe pool. Can I do this in exported state or must I "import -fN" ? I assume "zpool replace" is riskier in this case. Any special flags to make this operation safer?

2. I assume I would then run one of "zpool clear -F -n" or "zdb -cc -e -f (or -X)" or a simple scrub.

Thanks in advance for your advice.

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FreeBSD_amd64_12
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