As already noted there were quite a lot of Landwehr at Wagram. At Aspern Essling, the Landwehr units present looked like this:
1st Column (VI Corps) Hiller
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Nordmann's Advanced Guard
1st Vienna Volunteers – 544
2nd Vienna Volunteers – 610
Kottulinsky's Division
4th Vienna Volunteers – 269
Vincent's Division
3rd Moravian Volunteers – 1,057
3rd Vienna Volunteers – 547
2nd Column (I Corps) Bellegarde
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None
3rd Column (II Corps) Hohenzollern
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None
4th Column (part of IV Corps) Dedovich (under Rosenberg)
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Dedovich's Division
2nd Moravian Volunteers – 933
5th Column (part of IV Corps) Hohenlohe (under Rosenberg)
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Rohan's Division
Carneville Freikorps (Infantry) – 208
Carnevile Freikorps (Cavalry) – 115
Note: These were "irregular" troops, not technically Landwehr
I Reserve Corps – Liechtenstein
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None
Source: John H. Gill – 1809 Thunder on the Danube – Volume II – Aspern; Ian Castle – Osprey Campaign Series #33 – Aspern & Wagram 1809
Note: Bowden & Tarbox – Armies on the Danube 1809 is a much older piece of research (1st Edition 1980; 2nd Edition 1989) and for Aspern lists most of the above Landwehr formations but not all and also presents a different, older interpretation, of the Austrian command structure.
Nick