Short answer: No. In Paryushan (and in general Jain practice), onion powder and garlic powder are not eaten.

Why:

• Jains avoid root vegetables (like onions, garlic, potatoes, turnips) because uprooting roots harms living organisms and these foods are considered non-sattvic.
• Onion and garlic powders are simply processed forms of onion and garlic, so they are treated the same as eating the fresh items.
• During Paryushan, many Jains observe stricter dietary rules and thus avoid these items even more rigorously.

Note on traditions:

• Both Digambar and Śvetāmbara communities generally follow the root-vegetable avoidance. There can be local or guru-guided variations in everyday practice, but the standard guidance during Paryushan is to abstain from onion and garlic in any form.

If you’d like, I can share a simple, root-vegetable–free pantry list for Paryushan.