pyglossary ./Downloads/bulbagarden_en_all_maxi_2022-02.zim bulbagarden_en_all_maxi_2022-02.slob
Conversion is successful, aside from these two errors:
[ERROR] Aard2 slob: unknown content type for 'favicon'
[ERROR] resource title: mw/skins.minerva.base.reset|skins.minerva.content.styles|ext.cite.style|site.styles|mobile.app.pagestyles.android|mediawiki.page.gallery.styles|mediawiki.skinning.content.parsoid.css
and indeed, looks like some css and javascript didn't make it through (perhaps something pyglossary can improve), but text and pictures are there. Missing CSS can be added as user style as a workaround.