When you have a Search Replace List filter, the choice exists between using an External file or Using these values.
When using Find type = Perl, you can specify Enable UTF-8 Support.
Unfortunately, it would seem that UTF-8 support works only for External file, but not for Using these values.
At least, that's been my experience for a long while.
When I paste in characters beyond U+007F - it seems to treat the replacements as other than UTF-8.
Is this just me, or is this a bug?