您似乎正在使用一个库，但引用了另一个库的文档。

• https://github.com/nolimits4web/swiper（正式）
• https://github.com/surmon-china/vue-awesome-swiper

您正在从swiper/vue导入库，因此它必须是正式的库;在这种情况下，访问Swiper示例的方式略有不同：您需要存储Swiper示例。（参见控制器模式）。因此在您的情况下：

<template>
  <swiper
    style="border: 1px solid red; width: 400px"
    :slides-per-view="1"
    @swiper="onSwiper"
  >
    <swiper-slide>Slide 1</swiper-slide>
    <swiper-slide>Slide 2</swiper-slide>
    <swiper-slide>Slide 3</swiper-slide>
    <swiper-slide>Slide 4</swiper-slide>
  </swiper>

  <button @click="handleSlideTo">slide to 4</button>
</template>

<script>
import { Swiper, SwiperSlide } from "swiper/vue";
import "swiper/swiper-bundle.css";

export default {
  name: "App",
  
  components: {
    Swiper,
    SwiperSlide,
  },

  data() {
    return {
      swiper: null,
    };
  },

  methods: {
    onSwiper(swiper) {
      this.swiper = swiper;
    },

    handleSlideTo() {
      this.swiper.slideTo(3);
    },
  },
};
</script>

不要与其他库使用ref（vue-awesome-swiper）相混淆。

如果您使用的是<script setup>，则可以这样做：

<script setup>
  import { ref } from 'vue'
  import { Swiper, SwiperSlide } from 'swiper/vue'

  import 'swiper/css'

  const swiperInstance = ref()

  function onSwiper(swiper) {
    swiperInstance.value = swiper
  }

  function goToSlide(position) {
    swiperInstance?.slideTo(position)
  }
</script>

<template>
  <button @click="goToSlide(3)">
    Go to slide 3
  </button>

  <Swiper @swiper="onSwiper">
    <SwiperSlide v-for="i in 4">
      Slide {{ i }}
    </SwiperSlide>
  </Swiper>
</template>