Ah. y, i was concentrating more on the variable to filehandle issue rather than the actual data format.. Could still join it, though--just need an extra step to the join.. something like:

my @data = qw/AAAAAAAAAAAAAAA AAAAAAAGGAAACCA/;
my $ct = 0;
my $data = join '', map { sprintf ">Seq%d\n%s\n", ++$ct, $_ } @data;
my $SH = new IO::Scalar \$data;
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