[1.10.2] Setting Player Speed in hitEntity(...)

I'm trying to remake a mod I made a while back to 1.10, and quite a few of the items in it set the player's speed in some way. I was working on the simplest one: a sword that launches both you and your target in the air. I used this code:

package henryrichard.epicwasteoftime.item.tool;

import henryrichard.epicwasteoftime.EWOTMain;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.item.ItemStack;
import net.minecraft.item.ItemSword;

public class UpliftingSwordItem extends ItemSword {

public UpliftingSwordItem(String unlocalizedName, String registryName, ToolMaterial material, CreativeTabs tab) {
	super(material);
	this.setUnlocalizedName(EWOTMain.MODID + "." + unlocalizedName);
	this.setRegistryName(registryName);
	this.setCreativeTab(tab);

}

public UpliftingSwordItem(String unlocalizedName, String registryName, ToolMaterial material) {
	this(unlocalizedName, registryName, material, CreativeTabs.COMBAT);
}

public boolean hitEntity(ItemStack item, EntityLivingBase target, EntityLivingBase player)
    {
	target.motionX = 0D;
        target.motionY = 1D;
        target.motionZ = 0D;
        
        player.motionX = 0D;
        player.motionY = 1D;
        player.motionZ = 0D;

        item.damageItem(1, player);
        return true;
    }

}

However, this only sets the target's speed, and not the player. In 1.8 I could use this code:

((EntityPlayerMP)player).playerNetServerHandler.sendPacket(new S12PacketEntityVelocity(player));

However, this no longer works in 1.10.2 (It probably was removed in 1.9, but I haven't worked with that at all). Does anyone know how to fix this?