props to data

<template>
    <div>
        <p>{{category}}</p> //afisa obiectul de categorie OK
        <p>{{localCategory}}</p> //afisa obiect gol {}
    </div>
</template>

props: {
    category: {
        type: Object,
        required: true
    }
}
data () {
    return {
        //localCategory: Object.assign({}, this.category)
        localCategory: JSON.parse(JSON.stringify(this.category))
    }
}

//partinte
data() {
    return {
        category: {}
    }
},
created() {
    this.$store.dispatch('category/fetchCategory', this.$route.params.id)
    .then((response) => {
       this.category = response
    })
    .catch(error => {
       console.log(error)
    })
}