Is There an Unsweetened Version?

It depends on what you are actually looking for.

Powders sold in Japan as green tea are generally matcha or powdered green tea with sugar. In that sense, sweetness is the defining feature.

English usage is different: green tea covers all unoxidized tea — sencha, gyokuro, bancha — none of which is sweetened.

So if you want something unsweetened, what you are looking for is matcha or leaf tea, not a sweetened powder.

Diluting is not the same as removing

If you already have a sweetened product, using less powder reduces total sugar. The proportion stays identical.

You get a mildly sweet drink, not an unsweetened one. Removing sugar requires a different product.

Unsweetened options

Matcha — stone-milled tencha. Bitter, astringent, savory. Dissolves in water or milk, and you add sweetness if you want it. Combined with milk it makes an unsweetened latte.

Powdered green tea — ground sencha or similar. Cheaper than matcha, more astringent, less umami.

Loose-leaf green tea — more effort, but water temperature gives you control over the result.

"Lightly sweetened" claims

Terms like reduced sugar are comparative and have no fixed threshold. The nutrition panel is where the actual figure lives.

If you want to manage sweetness precisely, starting unsweetened and adding your own is the more controllable route.