Tapion possesses a sword that looks curiously like the one carried by Trunks' future counterpart. Over the course of the movie, Tapion and Trunks develop a bond, and after Hirudegarn's defeat, Tapion gives the sword to Trunks.

Where did Future Trunks get his sword from?

It is stated that Tapion did give his sword to Future Trunks in the video games Dragon Ball: Raging Blast and Dragon Ball Z: Battle of Z, with the latter mentioning that Tapion gave it after sealing Hirudegarn.

What kind of sword does Trunks use?

The Brave Sword (ブレイブソード, Bureibu Sōdo) is an enchanted sword owned by Tapion during the events of Dragon Ball Z: Wrath of the Dragon. This blade is given to Trunks at the end of the movie, and later used in the Dragon Ball GT opening.