Fair point but even if they have the distance advantage but as they have knowledge of itach, itachi has some knowledge on them since they are kage. Dusk crow doesn't require eye contact and we have seen that itachi is agile enough to both block and dodge sand attacks. Gaara doesn't have the ability to drag itachi out of susano'o this time (if he does, he would have to catch him off gaurd). Also,even if they alread y know about his gen it will be tricky to overcome. Agreed that they win though.
As i said once, I'll say it again Garra is Itachi's worse match-up in the series, besides obviously OP shinobi.
Garra's ability attack and defend simultaneously would critical in this match-up. Itachi's low stamina in trying toavoid sand and land a hit would be a challenge.
Genjutsu is obviously tricky, but Garra's distance has the ability to grant him the opportunity to avoid/ counter this without a problem. Genjutsu has never been shown as a long distance attack, so there is no way in proving otherwise.
Sending crows they get stomped easily, As garra would see them approaching
Overall i think Itachi is a bit stronger of course, but Garra has his advantages