for my $target (@Accession) {

}

##</code><code>##

    my @found = grep /$match/, @GI;

##</code><code>##

use strict;
use warnings;
use Data::Dumper;

my @GI = (
    'gi|Q384722390|emb|WP_938420210.1|Gene name',
    'gi|342546780|emb|WP_934203412.1|Gene name',
);
my @Accession = ( 'WP_938420210.1', 'WP_934203412.1' );

for my $match (@Accession) {
    my @found = grep /$match/, @GI;
    print "$match\n", Dumper [ split /\|/, $_ ] for @found;
}

##</code><code>##

use strict;
use warnings;
use Data::Dumper;

my @genes = (
    'gi|Q384722390|emb|WP_938420210.1|Gene name',
    'gi|342546780|emb|WP_934203412.1|Gene name',
);

my @accession = ( 'WP_938420210.1', 'WP_934203412.1' );

my %genes = map {
    my @s = split /\|/, $_;
    ( $s[3] => [@s] );
} @genes;

print Dumper \%genes;

# list the 2nd field from each gene
for (@accession) {
    print $genes{$_}[1], $/;
}