1、先看效果

2、以hooks方法处理，方便复制使用，见代码

Good.vue文件

<script setup lang="ts" name="goods">
  import {onMounted, ref, nextTick} from "vue";
  import useProductScroll from "@/utils/hooks/useProductScroll.ts";
  import loading from '@/assets/images/loading.gif'
  import categoryHolder from './images/category-holder.png'
  import productHolder from './images/product-holder.png'

  const productList = ref<any[]>([])
  const refSide = ref()
  const refMain = ref()
  const {mark, setMark, setRefSide, setRefMain} = useProductScroll()

  onMounted(() => {
    // 模拟productList的数据
    const tmpList = Array(15).fill(1).map((v, i) => {
      return {
        name: `人气热卖${i}`,
        pList: Array(5).fill(1).map((v2, i2) => {
          return {
            name: `名字${i}-${i2}`
          }
        })
      }
    })
    setTimeout(async () => {
      productList.value = tmpList
      await nextTick()
      setRefSide(refSide.value)
      setRefMain(refMain.value)
      setMark(tmpList[0].name)
    }, 200)
  })

</script>

<template>
  <div class="product-limit">
    <ul class="category-box" ref="refSide">
      <li v-for="v in productList" :key="v" :class="{'active': v.name===mark}" @click="() => setMark(v.name)" :mark="v.name">
        <div>
          <van-image :loading-icon="loading" :src="categoryHolder" lazy-load />
        </div>
        <span>{{v.name}}</span>
      </li>
      <li></li>
    </ul>
    <div class='right-content'>
      <div class="search-box">
        <van-search shape="round" placeholder="请输入商品关键词" />
      </div>
      <ul class="com-product-list" ref="refMain">
        <li v-for="v in productList" :key="v" :mark="v.name">
          <div class="c-category-name">{{v.name}}</div>
          <div class="c-detail-box" v-for="v2 in v.pList" :key="v2">
            <div class="img-show">
              <van-image :loading-icon="loading" :src="productHolder" lazy-load />
            </div>
            <div class="product-tro">
              <p class="c-name">{{v2.name}}</p>
              <p class="c-cut-money">
                <span>立省11.00元起</span>
              </p>
              <div class="c-money">
                <div class="c-money-detail">
                  ¥&nbsp;<i>5.60</i>起&nbsp;
                  <span>¥19.62</span>
                </div>
                <span class="c-btn-size">选规格</span>
              </div>
            </div>
          </div>
        </li>
        <li class="product-holder"></li>
      </ul>
    </div>
  </div>
</template>

useProductScroll.ts文件

import {ref} from "vue";

function getDomStyle(dom: HTMLElement, style: any) {
  return window.getComputedStyle(dom, null)[style];
}

const catchMainMarkDom: {
  [mark: string]: {
    dom: HTMLElement,
    top: number
  }
} = {}
const catchSideMarkDom: {
  [mark: string]: {
    dom: HTMLElement,
  }
} = {}
const catchMainMarkTop: number[] = []
const sideDomView: {
  [key: string]: number
} = {}
let timer:any = null
let io:any = null

export default function useProductScroll() {
  const mark = ref('')
  const refSide = ref()
  const refMain = ref()

  const setRefSide = (d: HTMLElement) => {
    if (getDomStyle(d, 'position') === 'static') {
      d.style.position = 'relative'
    }
    refSide.value = d
    // 判断是否在可视区域
    io = new IntersectionObserver(entries => {
      for (let i=0; i<entries.length; i++) {
        const dom = entries[i].target
        const m = dom.getAttribute('mark')
        sideDomView[m as string] = entries[i].intersectionRatio
      }
    });
    // 缓存
    const children: any = d.children
    for (let i=0; i<children.length; i++) {
      const dom = children[i]
      const mName = dom.getAttribute('mark')
      if (mName) {
        io.observe(dom);
        catchSideMarkDom[mName] = {
          dom: dom,
        }
      }
    }
  }

  const setRefMain = (d: HTMLElement) => {
    if (getDomStyle(d, 'position') === 'static') {
      d.style.position = 'relative'
    }
    refMain.value = d
    // 缓存
    const children: any = d.children
    for (let i=0; i<children.length; i++) {
      const dom = children[i]
      const mName = dom.getAttribute('mark')
      if (mName) {
        catchMainMarkDom[mName] = {
          dom: dom,
          top: dom.offsetTop
        }
        catchMainMarkTop.unshift(dom.offsetTop)
      }
    }
    // 绑定
    refMain.value.addEventListener('scroll', bindMainScroll)
  }

  const setMark = (str: string) => {
    mark.value = str
    const dom = catchMainMarkDom[str]['dom']
    dom.scrollIntoView({
      behavior: "smooth"
    });
  }

  const bindMainScroll = (e: any) => {
    clearTimeout(timer)
    const scrollTop = e.target.scrollTop
    timer = setTimeout(() => {
      // 判断top值和scroll比较，获取最近的top值，获取新的mark值
      let newTop = 0
      for (let i=0; i<catchMainMarkTop.length; i++) {
        if (scrollTop >= catchMainMarkTop[i]) {
          newTop = catchMainMarkTop[i]
          break;
        }
      }
      let markName = ''
      // 通过newTop值，获取新的mark名称
      for (let mName in catchMainMarkDom) {
        if (catchMainMarkDom[mName]['top'] === newTop) {
          markName = mName
          break
        }
      }
      if (mark.value === markName) return;
      mark.value = markName
      const isView = sideDomView[markName] > 0
      if (!isView) {
        catchSideMarkDom[markName]['dom'].scrollIntoView({
          behavior: "smooth"
        });
      }
    }, 200)
  }

  const unbind = () => {
    refMain.value.removeEventListener('scroll', bindMainScroll)
    io?.disconnect()
    io = null
  }

  return {
    mark,
    setMark,
    setRefSide,
    setRefMain,
    unbind
  }
}

3、使用，hooks抛出了5个方法，作用分别是：
mark：标示字符，用于判断分类

setMark：当分类点击时，传入mark值

setRefSide：传入dom元素，分类的scroll元素

setRefMain：传入dom元素，商品的scroll元素

unbind：组件卸载时调用

4、使用规则

a、用原生滚动

b、需要在页面渲染后使用

c、依次调用setRefSide，setRefMain，setMark

d、在分类列表和产品列表，scroll元素的子元素，需要绑定mark标示，用于匹配