If you need a truly zero-cost solution, use Ink/Stitch in Inkscape. If you need the i2 Plugin specifically for free, stick to the 30-day trial.
Once installed, the i2 menu appears on your top Illustrator toolbar. You can draw a line and instantly convert it to a running stitch. Draw a shape and fill it with Tatami (fill) or Edge Satin. The stitching updates live as you edit anchor points. Embroidery I2 Plugin For Adobe Illustrator Free Download
This is the core of your search query.
Tools like InkStitch (for Inkscape) offer free digitizing capabilities, though they are not native to Adobe Illustrator. If you need a truly zero-cost solution, use
Go to the Pulse Microsystems website (avoid third-party download sites). Navigate to "Products" > "i2" > "Free Trial." You can draw a line and instantly convert
Remember: The best free download is the legal one. Go to the Pulse website, grab your 30-day key, and turn your vector paths into stitch files in seconds.
Most "free" downloads fall into two categories: