[henry jiggy]

1-Get player weapon data storing it in variables
2-use ResetPlayerWeapons
3-give back all weapons except the one you want to remove

P.S: Weapon Data is tricky and annoys, but this is possible ^^

https://sampwiki.blast.hk/wiki/GetPlayerWeaponData
https://sampwiki.blast.hk/wiki/ResetPlayerWeapons
https://sampwiki.blast.hk/wiki/GetPlayerWeapon

EDIT:

Use GetPlayerWeapon to see the weapon the player is holding and give it to the other player, then the method above.