This works:

#!/usr/bin/perl6
use Inline::Perl5;
use Term::ANSIColor:from<Perl5> <color RED RESET>;

my $Red   = color("red");
my $Reset = color("reset");
say $Red ~ "--Red--" ~ $Reset;
say RED  ~ "--Red--" ~  RESET;
say "{RED}--Red--{RESET}";

# And Laurent_R is right:
my $Blue  = Term::ANSIColor::color("blue");
say $Blue ~ "--Blue--" ~ $Reset;
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Update: Another approach which works:

my $p5 = Inline::Perl5.new;
$p5.use('Term::ANSIColor');
my $Green = $p5.call('Term::ANSIColor::GREEN');
say $Green ~ "--Green--" ~ $Reset;
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However, this doesn't work (was trying to get around the AUTOLOAD):

Term::ANSIColor.YELLOW; # AUTOLOAD should generate YELLOW
my $Yellow  = Term::ANSIColor::YELLOW;  # Hmm, nope :(  at least not v
+isible to Perl6
say $Yellow ~ "--Yellow--" ~ $Reset;
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