The product is at the design stage.

产品处于设计阶段。

《牛津词典》

This tool is currently in the design stage.

目前该工具还处于设计阶段。

youdao

Comparing estimations as the model matures, at the design stage.

在设计阶段将模型当做成熟的形式估计。

youdao

It takes the company only 10 to 15 days to go from the design stage to the sales floor.

FORBES: The Future Of Fashion Retailing: The Zara Approach (Part 2 of 3)

Shaped like domes, jellyfish, spaceships and icebergs, few of these notions of futuristic dwellings will ever go beyond the design stage.

FORBES: 10 Floating Homes Of The Future

Matsushita also works closely with kyoei gaisha individually, sharing key technologies and bringing them in early at the design stage of production.

ECONOMIST: Business-to-business in Japan