Fair is the safest way to knock pikmin off you imo.
Depends on how they're lined up, and if you're in kill % or not.
not in kill % play normally VS the blues and be ready to shield/dodge purples.
if you're in kill % this becomes a little more tricky.. they're more likely to want to grab with the blues so be warry about that or wait for them to throw them/waste them in aerials/whiffed or spacing moves.
when they have the purple take note that your fsmash outranges purple grab and dash upsmash, and I THINK purple fsmash.
be warry of purple dsmash though.
ALWAYS ALWAYS PAY ATTENTION TO HIS PIKMIN ORDER unless its full of stuff of pikmin whose grabs can't kill you imo. [yellow,red,white].
Always pay attention when he has a yellow because thats one of the few times you can actually throw a FCAS under his pikmin tosses.
Blues are the most annoying pikmin in this MU.
SDI out of uair the opposite direction of which he's moving plus up, or just up if you can tap a lot of imputs.
I used to be able to falling dair to punish olimar after DIing upair sometimes but I can't do that anymore for some reason, trying to look for it again.
Uptilt and nair are weird, idk how to DI out them effectively. DI nair up when its falling nair though so you can dair/airdodge upsmash
Always be careful at being directly above him past 110, upsmash OOS it nuts.
Stay at a 90 degree angle at him or very close to him and MAKE YOUR JUGGLE TRAPS COUNT.