[fasterthanlime]

Yes (more like squashfs, which is what AppImage is, I forgot to mention that), although honestly the border between "filesystem images" and "archives" is tenuous.

[LoganDark]

I've created read-write DMGs with Disk Utility because you can encrypt them with a password. Basically first-party VeraCrypt without FUSE.

Though, when my MacBook broke and I had to switch back to Windows, I had to migrate it into an actual VeraCrypt volume.

The tool I used for this... was mounting the volumes on both machines and then using SFTP to copy the files themselves.