so any one think that usop might be able to imbue haki in his weapons like the amazon's arrows
In the future, anything is possible. After the TS, no. Heracles shows no sign of using Haki. He deals with strength and apparently special munitions.
Only Luffy and possibly Zoro will come out of the TS with some Haki prowess. Sanji won't have it either since Ivan hasn't shown any Haki abilities ( or he would've faired better against Magellan )
nor has anyone who does O.K.
I have mixed feelings about what Zoro did. One one hand i hate it that he went to the man he wants to surpass for help, Mihawk found it ridiculous too. However, i appreciate why he did it. Once again Zoro puts his friends before his pride, something that few have the character to do.