Federated directory of social services - could Façade-X help?

Dear Data Façades Community Group,

I am following your work with curiosity and wanted to reach out regarding
an upcoming project. As a freelance software developer I will be working
with the Civic Data Lab, a Ministry-funded NGO in Germany. The goal is to
create a federated directory of social counseling services in Germany. We
will fetch data from the databases of various organisations that
already maintain parts of this directory. The plan is to convert
the heterogeneous sources (we expect a mix of APIs with JSON output, HTML
scraping, CSV files, etc.) into one RDF schema. This schema will build on
existing vocabulary (e.g. the Core Public Organisation Vocabulary from
SEMIC) and gradually mature as we solve the challenges of integrating all
these sources while simultaneously working on the usage scenarios of this
new federated directory. So our challenge will be exactly as you put it: a
"homogeneous view over heterogeneous data sources."

Is the Façade-X method something I could use here? What approaches would
you recommend? Which libraries are already usable?
I'd really appreciate your thoughts and advice on this.

Best regards
Benjamin Degenhart
www.linkedin.com/in/bdegenhart