If you check the Zircon repo, you will see that they are backing in a linux virtualization layer in the kernel, so i imagine they will use that to bootstrap android linux apps in Fuchsia as a staging process, until android apps are completely native in a second phase.

Chrome OS already runs Android, so it would be a matter of stitching the Chrome os shell into Fuchsia to have both running in Fuchsia. First with virtualization of Linux, and later without it.