I'm in the same boat as you (MLE, lots of work exp incl. in a US AI startup, just started freelancing journey). Here are some more client acquisition/marketing ideas:

• Have a popular open-source project (ML related) on github (takes time)
• Content marketing: Write articles/blog posts and promote those on LN
• Give talks on conferences/meetup
• Find established freelancers and ask to be a subcontractor
• Chase prospects on LN (e.g. identify a niche like "YC startup founders" follow them and engage in a conservation.

everyone: pm me if you want to connect on LN (or if you have a project for me 🤗)