Lakshya, seeded eighth, needed 59 minutes to overcome Weng 17-21 21-18 21-16 in the summit clash for his third successive singles title of the season.
He had clinched the Belgian International challenge and Dutch Open Super Tour 100 in his last two outings. He had also reached the Polish Open final this year.
World number 51 Sen, who has won the Asian Junior championship, a silver at the Youth Olympics and a bronze at World Junior Championship last year, continues to impress on the senior circuit.
The 18-year-old from Uttarakhand had come into the final with a 1-2 head-to-head record against the Chinese but it didn’t matter as he rallied his way after squandering the first game to complete a thrilling win here.
After this win, Lakshyaa is set to break into the top 50 when the BWF rankings are released on Tuesday.
Lakshya had a good start as he was leading 14-11 but he couldn’t sustain the pressure on his opponent who turned the tables to win the opening game.
Stung by the reversal, Lakshya jumped to a 8-4 lead in the second game. The Indian quickly moved to 13-6. Weng reduced it to 10-14 but Lakshya managed to stay ahead of his rival and take the match into the decider.
In the third game, Lakshya fell behind 5-7 but managed to claw back at 10-10 before Weng moved to a 16-13 lead.
A fighting Lakshya then stepped on the gas and reeled off the remaining eight points to leave his rival stranded.
Lakshya is likely to participate in two International Challenge events, the Irish Open (November 13-16) and Scottish Open (Nov 21-24) — before featuring in the Syed Modi International Super 300 (Nov 26-Dec 1).