Can I select files and restructure directories for release source file?

Question

I want to release a version of my project with selected files from sub-directories.

For an example, this is my GitHub Repository

SolarSystem
.
├── mercury
│   ├── object1.txt
│   └── object2.txt
├── venus
│   ├── partical1.txt
│   └── particle2.txt
├── earth
│   ├── computer.txt
│   ├── tree.txt
│   └── human.txt
├── mars
│   └── water.txt
├── .gitattributes
└── .git

and, gitattributes file for ignore files for release.

/.gitattributes  export-ignore
/mercury export-ignore
/venus export-ignore
/mercury export-ignore
/mars export-ignore
/earth/computer.txt export-ignore

With this, when I release a version -

SolarSystem.zip
.
├── earth
│   ├── tree.txt
│   └── human.txt

But I want to select few files without the sub-directory,

SolarSystem.zip
.
├── tree.txt
└── human.txt

How can I achieve this result? Is it possible to do with gitattributes config or I must to use GitHub Actions to achieve this ? Is this possible? Or is there a better/easier solution I'm missing?

I have tried export-subst and delta options but didn't achieve the result.