Yes, you can add users by using users-permissions services:
await strapi.plugins['users-permissions'].services.user.add({
blocked: false,
confirmed: true,
username: 'new_username',
email: 'test@testemail.com',
password: 'secretpassword', //will be hashed automatically
provider: 'local', //provider
created_by: 1, //user admin id
updated_by: 1, //user admin id
role: 1 //role id
});
All those from the above example.