Rusti,
There are a number of ways to look at this, but I'd ask you to think about whether you have a favourite campaign which the Austrians participated in (Revolutionary or Napoleonic). I'll just list a couple examples so you get the idea that it probably doesn't matter as long as you have the right painting reference material!
1805
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The Austrian Avante-Garde fought defensively against the French in a number of rear guard actions, both in Italy and in Austria. I'd suggest your French attacker would likely be a combination of French light cavalry/leger troops advancing in front of main French columns.
Alternatively, there was a couple skirmishes between advancing Austrians and a Bavarian force on the north perimeter of the 1805 campaign. The Bavarian force was mostly line infantry, supported by a light battalion (4 line for 1 light average ratio), supported by a couple regiments of chevaux-leger or 1 chevaux-leger and 1 dragoon regiment.
1809
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The Austrian Avante-Garde invaded Bavaria in early April and encountered Bavarian rear guard forces that slowed the Austrian advance. A prime example of this occurs around Altdorf, but there are a number of examples. The composition of the Bavarian force is similar to the one I described in the 1805 summary except more Bavarians were engaged on a regular basis. There was also a limited engagement against the Poles prior to and following Raszyn - but the level of minor skirmishing was minimal to justify buying Polish troops (they do look great though).
Alternatively, once Napoleon arrived and the campaign initiative belonged to the French, Radetzky's avante-garde operated as a rear guard (one example of a few). The Austrian avante-gardes in this case faced a number of different opponents including Wurttemberg light infantry/light cavalry, French cuirassiers, a variety of French light troops. You name it.
1814
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Schwarzenberg's hauptarmee advanced slowly along the upper Rhine and engaged Augereau's French troops at Mâcon, Saint-Georges-de-Reneins and Limonest on the way to Lyon. The subtle difference in 1814 (and 1813) is you'll see more French conscripts dressed poorly, some such as the Marie-Louise's were lucky to have a greatcoat and shako.
Summary
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You can paint and field whatever you like. If you are looking for troops that are "more commonly" used for this sort of engagement, I'd recommend sticking with French or Bavarian troops - mixture of infantry, light cavalry and a battery would be a great start. In campaign dress you could argue that no plumes are on the shako, shako covers are in use for protection against rain and you'll have very, very few reasons to paint French light versus line troops - generic French would also do in the greatcoats. If you prefer a splashier uniform then acquire some French line and leger and use them both. Think long term - statistically your French troops would be like the Romans and WWII Germans - they fought a lot, on a lot of different fronts, so your figures will be used more often in "historical" simulations that perhaps a satrap ally who contributes on secondary fronts for a small portion of a campaign.
Respectfully,
Michael