Chicks Dig Giant Robots
Anime
To qualify for this stack, the following must be true
1) The show includes some form of mecha, interpreted loosely.
2) The show must include one or more important female characters
3) At least one of the female characters, other than a villain, must interact directly with the mecha in an important role (typically pilot, but other roles can be sufficient)
This does not require that only females pilot or even that the main character/pilot must be female, only that we get a good active role from a female character, not just a damsel or sideline role.
1) The show includes some form of mecha, interpreted loosely.
2) The show must include one or more important female characters
3) At least one of the female characters, other than a villain, must interact directly with the mecha in an important role (typically pilot, but other roles can be sufficient)
This does not require that only females pilot or even that the main character/pilot must be female, only that we get a good active role from a female character, not just a damsel or sideline role.

TV, 2005,
12 eps
Me:-
Author:5
The central pilots are female as are most of the major ones overall
86
86 Eighty-Six

TV, 2021,
11 eps
Me:-
Author:10
Futuristic spider-tanks. Includes female pilots in the main group
86 Part 2
86 Eighty-Six Part 2

TV, 2021,
12 eps
Me:-
Author:10
Futuristic spider-tanks. Includes female pilots in the main group
Aoki Hagane no Arpeggio: Ars Nova
Arpeggio of Blue Steel -Ars Nova-

TV, 2013,
12 eps
Me:-
Author:7
Some of the girls are ultratech warships. A marginal include, but it's presented with enough techist trappings.
Bubuki Buranki
BBK/BRNK

TV, 2016,
12 eps
Me:-
Author:7
Includes female characters in the main pilot group (3/5)
Bubuki Buranki: Hoshi no Kyojin
BBK/BRNK: The Gentle Giants of the Galaxy

TV, 2016,
12 eps
Me:-
Author:8
Includes female characters in the main pilot group (3/5)

TV, 2018,
24 eps
Me:-
Author:7
All robots piloted by male-female pairs by default.
Ginga Kikoutai Majestic Prince
Majestic Prince

TV, 2013,
24 eps
Me:-
Author:7
Includes female characters in the main pilot group (2/5)
Gyakuten Sekai no Denchi Shoujo
Rumble Garanndoll

TV, 2021,
12 eps
Me:-
Author:5
Girls are necessary for the mecha to operate and determine its form.

TV, 2017,
12 eps
Me:-
Author:7
Some characters drive giant robots, some are giant robots, and in both cases some are female (including the lead)
IS: Infinite Stratos
Infinite Stratos

TV, 2011,
12 eps
Me:-
Author:6
Pilots are female by default with the MC as an exception
IS: Infinite Stratos 2
Infinite Stratos 2

TV, 2013,
12 eps
Me:-
Author:7
Pilots are female by default with the MC as an exception
Kakumeiki Valvrave
Valvrave the Liberator

TV, 2013,
12 eps
Me:-
Author:6
Includes female pilots in the main pilot team, male lead.
Kakumeiki Valvrave 2nd Season
Valvrave the Liberator 2nd Season

TV, 2013,
12 eps
Me:-
Author:6
Includes female pilots in the main pilot team, male lead.

TV, 2011,
13 eps
Me:-
Author:9
"Robots" are more mystical and are controlled rather than "piloted"; prominently includes female controllers alongside some male and a non-controller male protagonist.
Koukyoushihen Eureka Seven
Eureka Seven

TV, 2005,
50 eps
Me:-
Author:7
Includes points where a female pilots but skews male for the protagonists.
Megami Kouhosei
Candidate for Goddesses

TV, 2000,
12 eps
Me:-
Author:4
Male lead, but the current ace pilot is female.

TV, 2021,
12 eps
Me:-
Author:6
Male lead, most of the other pilots and trainees seen are female.

TV, 2022,
12 eps
Me:-
Author:7
Male lead, most of the other pilots and trainees seen are female.

TV, 2012,
24 eps
Me:-
Author:6
Male lead, most of the other pilots and trainees seen are female.

TV, 2019,
12 eps
Me:-
Author:5
Includes female characters in the main pilot group. Mini-mechs.

TV, 2009,
12 eps
Me:-
Author:7
Robot motorcycles are not exactly mechas, but features a central female lead to ride them.
Rinne no Lagrange
Lagrange: The Flower of Rin-ne

TV, 2012,
12 eps
Me:-
Author:6
Central mecha pilots are all female.
Rinne no Lagrange Season 2
Lagrange: The Flower of Rin-ne Season 2

TV, 2012,
12 eps
Me:-
Author:7
Central mecha pilots are all female.

TV, 2021,
12 eps
Me:-
Author:8
Includes female characters among the main pilot group.
Sousei no Aquarion
Aquarion

TV, 2005,
26 eps
Me:-
Author:6
Female leads occasionally pilot but are sadly sidelined.

TV, 2013,
12 eps
Me:-
Author:8
More of a techist magical girl affair, but close enough to be counted here.