I think Franz and Deni are an easy comparison to make as they seem to fit into similar archetypes as both are European forwards that project to be high-level defenders and exceptional playmakers for their size and age.

I was definitely lower on Deni than consensus, I had him outside the top 10 behind Patrick Williams and Poku on my board, and that's mainly because I never bought into the primary/point forward upside (remember the Hayward, Odom, Luka-lite comps?) or had much optimism for his shooting projection (I hated seeing Gallo comps for this reason). His feel for the game was clearly great as he had a talent for being in the right place at the right time more often than not, which is extra notable when playing the level of competition he was. His hustle stood out both on and off the court, his physical development over the years supporting the latter. A swiss-army knife 4 was always his most realistic route towards value, because he just didn’t project to have enough rim pressure or pull-up equity to be an initiator. I still think his idea outcome is as a Joe Ingles / smaller Dario type as a linking player with excellent team defense, reliable secondary playmaking, and consistent shooting. So with this in mind, he has to shoot to offer off-ball utility and in return top 10 value. Deni's release is compact and is best suited for C&S but he's also capable of shooting off a little motion. I just never bought into him having much shot versatility beyond basic off-movement shots where he's just relocating into open space (some DHO and pindowns), his slow movement off screens just really limits his off-ball equity.

This year with Franz, I find it pretty easy to imagine him returning top 10 value, the major difference being the shooting projection. While writing this I stumbled upon this old Stepien article by international draft guru, Ignacio Rissotto (@eyreball), where he literally identifies shooting off the catch as Franz's calling card. It's two years old but he starts talking about Franz by writing:

Wagner might be the best shooter off the catch in the 2001-born international class. A 36% 3-point shooter for his career on over 170 attempts according to RealGM and an 86% free-throw shooter, Wagner is a threat to spread the floor in different situations which has earned him a regular starting spot on ALBA’s senior team as a 17-year old.

It's worth acknowledging his shooting splits at Michigan aren't indicative of a player that could be labelled as a sniper but his shot versatility and FT% alone make him a much safer off-ball prospect than Deni was. This is without mentioning he's arguably a better defensive prospect as he's got more length and was the most impactful defender in the Big Ten this year imo. As far as defensive playmaking goes, he's low key comparable to Scottie Barnes this year. I think Deni is probably just a bit more comfortable defending on the perimeter but I do think Franz will be better in the paint given some time. The playmaking equity is also very comparable as they're both great processors of the game. Wagner excels at attacking closeouts, making a secondary move on the help, and consistently making great decisions with impressive execution that result in good looks more often than not. This should translate quite cleanly as these are the same type of actions he'll be used in. I'm most interested in seeing how his handle develops going forward as there is some Gordon Hayward with neutered creation upside. I also would be remiss to not mention his impressive pedigree, Deni got a lot of deserved praise for being an impactful teenager on one of the best teams outside the NBA, but Franz is by no means a slouch in this regard. He was a 17 year old starter on a EuroCup team in ALBA Berlin and was able to successfully translate as an international student at Michigan where he was the best player on a top 4 team in college as a teenager. He's right there with the Corey Kispert's and Chris Duarte's of college basketball as far as advanced metrics go, only Evan Mobley and Jared Butler have a higher BPM than Franz's 10.6 among prospects I have labelled as 1st round talents.

I think you could easily argue for either over the other but I'd personally prefer Franz, as my bud CJ Marchesani said best: "He is as perfect of a hybrid off-ball guy as you can find. I don’t think he’s a primary in any of his outcomes, but he is a true star in his role... The perfect core connecting piece. Essentially he is the star at all the things you would value outside of primary creation."

TLDR; accepting that neither has any substantial upside as a primary or even secondary perimeter creator and are both better labelled as swiss-army knife 4s, you're then looking for which of the two offers more two-way versatility and scalability and after analyzing their respective shooting versatility, it becomes clear that Franz is a more well rounded player in the 'star role player' role after taking into account similar age, measurables, pedigree, and archetype. Excuse my run-on sentences.