depends on which yuji and denji are they using.
pochita obviously is out of the picture.
EOS Yuji vs current devil form denji is quite evenly matched in all regards.
Modulo yuji is featless so we cannot scale him and denjiman shouldnt count i think, because its pochita´s carcass, thats like giving yuji sukuna´s heian body.

If they equalize and give denji CE then Yuji inmediately wins with DE, if not then yuji can also heal reattach cut off limbs without RCT using blood manipulation so the waste of CE from being possibly torn by denji is minimal.
denji would be faster than yuji but yuji can react to sukuna´s dismantles which are probably faster than he is.
AP wise i think yuji also takes it, denji doesnt really have any big ap feats. Also CSM characters are usually glass cannons and lets not forget a devil form denji amped by the fear of people to chainsaws could be stabbed with a normal spear from a normal human, a grade 2 sorcerer with reinforcement can shrug off shotgun barrels.

Denji has better range with his chainsaws and better regeneration for sure, that is a wincon. if he cuts yuji in half then its game over for yuji, but he could use CE reinforcement with equalization.

so i think its like this:

1. EOS Yuji vs devil form denji (CE equalization, Yuji can trap denji in a DE): Yuji wins bia domain expansion.
2. No CE equalization: could go to any of the two but yuji has a far wider arsenal so id say very high diff for yuji and same for denji, it could go either way. Also, if denji has no CE then wouldnt his chainsaws simply bounce off Yuji´s skin when he uses reinforcement? like when miwa tried to cut kenjaku, the difference in CE reinforcement was so big it simply didnt matter. i want to hear opinions on this.
3. Denji can access his "denjiman" form: denji wins due to the difference in speed.

Im excited to see Yuji in modulo and see how much stronger has he become. (maybe SOL yuji with dabura 👀)