How to run migrations with dynamic schemas?

Question

I'm using Sequelize (Postgres) and I'm trying to dynamically create schemas and run migrations in them. In other words, I'm not using sequelize.define, because I have no purpose for it. I create the migrations with npx sequelize-cli model:generate and I want to run the migrations with npx sequelize-cli db:migrate.

However, this keeps throwing the error,

ERROR: no schema has been selected to create in

I've tried instantiation sequilize as so,

// at this point, the schema already exists
const sequelize = new Sequelize(sequelizeConnectionString(schema.schema_name)); // generates dynamic connection string with required schema
await sequelize.authenticate();
// . . . logic for generating
// . . . the migrations with
await sequelize.sync(); // no error thrown

But this doesn't do anything.

How can I take my dynamically generated migration scripts and run them with npx sequelize-cli db:migrate with the needed schema?