Is it OK to send gift to a person who is "Currently trade banned"?

I would just request a new winner..

That's acually a good question i'm not sureabout steamgifts but I would request a new winner personally. People like that should learn to behave. No scams, no cheats, no abuse therefore good promoting of the rules.

Pretty sure you have to give it to them since there is no rule against exploiters, scammers and cheaters joining sg... Only rules against humming, wearing socks and sandals together, wearing brown pants, eating ice cream on Thursdays, etc..., you know... all the really important stuff.

Don't even think you're allowed to have rules on public giveaways (you know, like no scammers allowed, etc...) unless the mods agree to them..

I'm not sure steamgifts has any rules against it. I think you can decide if you want to send the gift or not in this case. I know support will accept your request for a re-roll. So it's up to you.

Request a reroll. I requested before because the winner didn't have a clean profile.

if they have a trade ban how can they be given the item tho

There's plenty of cases when you can receive a trade ban even if you have never traded, i.e. when you change steamguard options, change ISP or something alike... it's not about scamming or so (actually i don't think you get trade banned for scamming, since that usually occurs outside of valve trade system)...

It's been said already that a trade ban may not be due to scamming or other disruptive behavior. You could also have a look at the winner's steamtrades profile and their steamrep profile for additional hints. I'd suggest talking to them directly, if you can spare the time. In any case, the gift doesn't have to be traded, it can be sent via e-mail as well.

Personally, I wouldn't go for a reroll just for temporary trade ban, which I think could be due to Steamguard being off on the winner's account.