从网上看到的答案千篇一律，namespace跟路径等都是正确的，mybatis plus 官网提示修改配置，如下：

改造后配置 

import com.baomidou.mybatisplus.extension.plugins.MybatisPlusInterceptor;
import com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jdbc.DataSourceBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;

import javax.sql.DataSource;

/**
 * MybatisPlus配置
 * @author datszhang
 * */
@Configuration
@MapperScan(basePackages = {"com.*.cloud.base.mapper"})
public class MybatisPlusConfig {


    /**
     * mybatis-plus分页插件<br>
     * 文档：http://mp.baomidou.com<br>
     */
    @Bean
    public MybatisPlusInterceptor paginationInterceptor() {
        MybatisPlusInterceptor paginationInterceptor = new MybatisPlusInterceptor();
        return paginationInterceptor;

    }


    @Bean(name = "dataSource")
    @ConfigurationProperties(prefix = "spring.datasource" )
    public DataSource initDataSource () {
        return DataSourceBuilder.create().build();
    }



    @Bean("sqlSessionFactory")
    public SqlSessionFactory sqlSessionFactory() throws Exception {
        MybatisSqlSessionFactoryBean sqlSessionFactoryBean = new MybatisSqlSessionFactoryBean();
//        sqlSessionFactoryBean.setDataSource(multipleDataSource(lxcs(), lxcs1()));
        sqlSessionFactoryBean.setDataSource(initDataSource());
        sqlSessionFactoryBean.setPlugins(new MybatisPlusInterceptor());
        //解决绑定找不到问题
        sqlSessionFactoryBean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath*:xml/**/*.xml"));
        SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBean.getObject();

        return sqlSessionFactory;
    }
}

这样启动就没有问题了