Do you think businesses would benefit from an online course that teaches Spanish for business & insight on the Latin American customer in US?

I think you are missing the market research step. You need to ask the people that you would be targeting, because at the moment, I'm unsure why someone would use your product, over say using a platform where they can hire an online tutor and learn from them, or use Rosetta for example. I get that you have the learn about Latin Culture component, but are potential clients really falling over themselves to learn more more about this market, that they would pay for it, especially when google is so helpful.

Also, freelancers, entrepreneurs, business owners etc is a pretty large group, maybe start with narrowing that down, then asking them directly, if it would be something they want to buy, or you could also test the idea using something like Udemy.

If you need any further help with this, feel free to book a call with me!

Well, I know a lot about promoting language courses with business clients in mind!
The answer to your question is: Yes, businesses would benefit!
That, however, is just the beginning.
1) Your content has to be professional and offer something most language course providers don't offer (USP).
2) You target groupd seems clear - companies wanting to do business with the Spanish-speaking world - but you need to identify those companies. You need to do research here and network. LinkedIn is an obvious choice, but you want to filter effectively. For that, try out LinkedIn navigator or other add-on services (which you must pay for). There are, of course, also groups there that could be relevant.
3) You need to get people to know who you are and what you are offering (that's obvious).
There are a number of course platforms - like udemy and Teachable - where you can test your course(s) and even make some money in the process.
You can also post videos that provide an example of your course.
Give me a call. I can share my experiences with you!

No, I don’t think that’s a good idea. I DO believe it’s a great niche you are referring to, but I would go with other type of solution / product. The options you mention have too many huge competitors and I don’t think they would have a differentiation value.
I would be super glad to discuss it with a phone call. I am sure I can guide you (in whatever language you prefer: English or Spanish). Best!
Ana