You cannot generate an authentic Vakya chart on mainstream apps like AstroSage or Co-Star. You need specialized software or a traditional almanac.
Here is how to proceed:
Using Vakya Panchangam for a birth chart: vakya panchangam birth chart
Pros:
Cons:
Consider a person born on April 15, 1985, at 10:00 AM IST in Chennai, India.
Vakya Panchangam (Traditional Tamil):
Result: In the modern chart, this person is a Leo Lagna with Moon in Aquarius (friendly). In the Vakya chart, they are a Cancer Lagna with Moon in Capricorn (enemy sign). The predicted career, marriage timing, and health according to Vakya rules will differ completely from a Lahiri interpretation.