效果图如下：

直接附上全部代码

<script setup lang="ts">
import { ref, onMounted, nextTick } from 'vue'
import { ElInput, ElMessage } from 'element-plus'
const InputRef = ref<InstanceType<typeof ElInput>>()
let table = ref([])
const arr: any = ref([]);
let buttonIndex = ref<number | ''>('')
// 添加规格
function handleAdd() {
  let obj = { name: '', bool: false, count: 0, keys: [],};
  arr.value.push(obj)
  console.log(arr.value);
}

function handleCloseName(index:number){
  console.log(arr.value,arr.value[index]);
  
  arr.value.splice(index, 1)
   table.value.splice(index, 1)
  
}
const inputVisible = ref(false)
//删除规格值
const handleClose = (index: number, ind: number) => {

  arr.value[index].keys.splice(ind, 1)
  arr.value[index].count = arr.value[index].count - 1
}
//显示规格值输入框
const showInput = (index: number) => {
  if (arr.value[index].count == 3) {
    ElMessage({
      message: '规格值不能超过三个！',
      type: 'warning',
    })
    return false
  }
  inputVisible.value = true;
  buttonIndex.value = index;
  arr.value[index].bool = true;
  arr.value[index].count = arr.value[index].count + 1;
}

//刷新
function handleChange() {
  table.value=[]
  const keysList = arr.value.filter((item: any) => item.keys.length).map((item: any) => item.keys);
  const titles = arr.value.map((item: any) => item.name);
  if (keysList.length == 0) {
    arr.value.keys = [];
    return
  }
  console.log(keysList);
  var skuList = keysList.reduce((pre: string[][], next: any) => {
    var array: string[][] = [];
    pre.forEach(item => {
      next.forEach((ite: any) => {
        array.push(item.concat([ite]))
      });
    });
    return array
  }, [[]]);
  console.log(skuList, '----skuList-');
  var skuTable = skuList.map((item: any) => {
    const temp: any = {
      price: 0,//现价
      title: '',
      titleArray: [],
      specArray: []
    };
    item.forEach((val: any, index: number) => {
      var key = 'id' + titles[index];
      temp[key as keyof typeof temp] = val;
      console.log(val + '-----');
      temp.titleArray.push(val);
      temp.specArray.push(titles[index] + '_' + val);
    });
    temp.title = temp.titleArray.join(',');
    temp.specification = temp.specArray.join(',');
    return temp;
  })
  table.value = skuTable
  console.log(table.value, '----table.value');

}
//合并表格
const objectSpanMethod = ({ row, column, rowIndex, columnIndex }: any) => {
  //拿到第一列要合并的行数
  let specList = arr.value.filter((e: any) => e.keys?.length > 0);

  if (columnIndex < specList.length - 1) {//列下标小于规格数组长度减一
    let rowSpanNum = 1;//行
    for (let i = columnIndex + 1; i < specList.length; i++) {
      //依次拿到每一列要合并的行数
      rowSpanNum *= specList[i].keys.length;
    }
    if (rowIndex % rowSpanNum === 0) {
      //当条件成立时，即合并行数
      return { rowspan: rowSpanNum, colspan: 1 }
    } else {
      return { rowspan: 0, colspan: 0 }
    }
  }
}
</script>

<template>
  <div class="box">
    <div class="Specification-header">
      <el-row class="mb-4">
        <el-button type="danger" @click="handleAdd">+添加规格</el-button>
      </el-row>
    </div>
    <div v-for="(item, index) in arr" :key="item" class="Specification ">
      <el-input v-model="item.name" placeholder="填写规格" style="width: 300px;" />
      <el-icon class="input_icon" @click="handleCloseName(index)" :size="15" color="#ccc">
        <CircleClose />
      </el-icon>
      <el-button class="button-new-tag ml-1" size="small" @click="showInput(index)">
        添加规格值
      </el-button>
      <div class="tag">
        <div class="input" v-for="(i, ind) in item.count">
          <el-input v-if="inputVisible && item.bool" placeholder="填写规格值" ref="InputRef" v-model="item.keys[ind]"
            :value="item.keys[ind]"  style="width: 100px;" />
          <el-icon class="icon-CircleClose" @click="handleClose(index, ind)" :size="15" color="#ccc">
            <CircleClose />
          </el-icon>
        </div>
      </div>
    </div>
    <el-card class="box-card">
      <template #header>
        <div class="card-header">
          <el-row class="mb-4">
            <el-button type="danger" @click="handleChange">刷新</el-button>
          </el-row>
        </div>
      </template>
      <el-table :data="table" :span-method="objectSpanMethod" style="width: 100%" border>
        <el-table-column v-for="(item, index) in arr.filter((item: any) => item.keys.length)" width="100" align="center"
          :prop="'id' + item.name" :label="item.name" />
        <el-table-column label="销售价" width="180">
          <template #default="scope">
            <el-input-number v-model="scope.row.price" :min="1" />
          </template>
        </el-table-column>
      </el-table>
    </el-card>
  </div>
</template>

<style scoped>
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.Specification {
  position: relative;
  width: 450px;

}

.input_icon {
  position: absolute;
  right: 0px;
  z-index: 999;
}

.box-card {
  margin-bottom: 20px;
  width: 600px;
}

.input {
  height: 40px;
  margin: 5px;
  position: relative;
}
.Specification-header{
  margin: 10px 0px;
}
.icon-CircleClose {
  position: absolute;
  left: 90px;
  z-index: 999;

}

.tag {
  width: 200px;
  height: 50px;
  display: flex;
  justify-content: start;
}
</style>

注：刷新按钮可以换成计算属性，这样就不用每次点刷新。