Your videos and learning modules are wonderful, I commend you for putting together a simple and easy-to-navigate resource for FFN care providers. Our population of FFN has very limited access to computers and internet, and many do not have smart phones, so we have not yet invested in online learning or video tools. While it's not free, we do know of an app called Kinedu, it has developmental questionnaires and activities for parents in Spanish that could easily be translated to an FFN setting. We've also found resources on http://Zerotothree.org in Spanish - https://www.zerotothree.org/resources?q=&topic=&type=&rformat=&age_range=&lang=es
Believe it or not, Sesame Street also has a lot of content in Spanish on their website! I'm not sure if that would be along the lines of what you're looking for, but it may be a helpful resource when developing your own content in Spanish.
Your project is very interesting, and it seems that your work would translate to our setting quite well. I would be interested to know if you have created specific programs that address two-generation learning - that is, for parents and their very young children ages 0-3 to engage in your sound therapy together, and if so, what were the outcomes of that work on children's social emotional development?
We would be very interested to see how your project progresses and if you are able to bring it to low-income Latino communities in the US, since that is the population we serve as well!