Feel free to correct me if I'm wrong, but:
Sarevok's portrait wasn't in BG1, so you won't be able to import it from there. Since he does appear in ToB, it should be possible for you to import it from there (if you even need to import it)
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The last arrow of Legolas kindled in the air as it flew,
and plunged burning into the heart of a great wolf-chieftain.
All the others fled. -J.R.R. Tolkien, The Lord of the Rings
