Group objects rotation and origin setting

[OlGF]

Hello, 

I've just started learning Phaser 3. Playing with simple code and it seems my approach is not good.
Here is example what I'm trying to implement (moving and firing tank):

I used two separate sprites to animate tank and its shooting. Then I decided to complicate tank behavior during the shoot, so now it imitates recoil by rotating both of sprites (tank and shoot).
I found no way to rotate group of sprites at once, so I'm rotating it one by one. Also I had to use dirty workaround with changing sprite origins to have same angle at rotation.

I guess the better way to do the same would be a single sprite which includes both moving and firing frames. But probably code below may be improved. Any advice is highly appreciated:

    var config = {
        type: Phaser.AUTO,
        width: 1000,
        height: 600,
        physics: {
            default: 'arcade'
        },
        backgroundColor: "#007236",
        scene: {
            preload: preload,
            create: create,
            update: update
        }
    };

    var game = new Phaser.Game(config);
    var tankGroup, tank, cursors, fire;
    var shooting=0;

    function preload ()
    {

        
        this.load.spritesheet('tank', 'assets/tank.png',{ frameWidth: 200, frameHeight: 200 });
        this.load.spritesheet('shoot', 'assets/shootfire.png',{ startFrame: 8, frameWidth: 16, frameHeight: 16 });
    }

    function create ()
    {

        tankGroup = this.physics.add.group();
        tank = tankGroup.create(900, 100, 'tank');
        fire = tankGroup.create(908, 98, 'shoot',7);
        fire.setOrigin(6,1);
        tank.setOrigin(0.5,0.5);
        fireSound=this.sound.add('fire');

        
        tank.flipX=true;



        this.anims.create({
            key: 'shoot',
            frames: this.anims.generateFrameNumbers('shoot',{start: 0, end: 7}),
            framerate: 7,
            repeat: 0
        });

        this.anims.create({
            key: 'moving',
            frames: this.anims.generateFrameNumbers('tank',{start: 0, end: 2}),
            framerate: 1,
            repeat: -1
        });

        cursors = this.input.keyboard.createCursorKeys();

    }

    function update() 
    {
        if (cursors.left.isDown){
            tankGroup.setVelocityX(-30);
            tank.anims.play('moving', true);
        } 
        else if (cursors.right.isDown){
            tankGroup.setVelocityX(30);
            tank.anims.playReverse('moving', true);
        } else {
            tankGroup.setVelocityX(0);
            tank.anims.stop();
        }
        
        if ( Phaser.Input.Keyboard.JustDown(cursors.space) ){
            shooting=1;

            fire.anims.setTimeScale(0.5);
            fire.anims.play('shoot');
        }
        
        tankRecoil();

    }

    function tankRecoil(){
        if (tank.angle<=10 && shooting==1){
            tank.angle+=1.8;
            fire.angle+=1.8;
        } 
        
        if (tank.angle>10)
            shooting=2;
        
        if (tank.angle>0 && shooting==2){
            tank.angle-=0.8;
            fire.angle-=0.8;
        } 
        
        if (tank.angle<=0 && shooting==2){
            shooting==0;
        } 
        
    }