I follow Euroleague basketball a lot and a part of the process of following so many games and players I see a lot of change.
First off let’s definte the two above mentioned positions in the title and get going from there.
Both are dubbed or rather mentioned by Eric Stang in his 3rd Ed. book called Scouting Techniques that can be bought online:
“Modern Center
Attributes:
-Fluid athlete
-Has the ability to help stretch the floor.
-Moderate ball-handling ability.
-Not physically imposing more mobile center.
-Versatility is above average.
Skill Set:
(+) Threat as a roller.
(+) Have to respect outside shooting ability. (+) Versatile on both ends.
(-) Ball-handling and creating off the dribble. (-) Playmaking and IQ.
Classic Center
Attributes:
-Great size.
-Places pressure on the rim at both ends.
-Limited defensive versatility.
-Excels at rebounding.
-Low FGA with a high FGM%.
Skill Set:
(+) Roller.
(+) Paint touch shots.
(+) Setting screens.
(+) Rebound position.
(-) Ball handling.
(-) Passing ability.
(-) Low agility level
The Examples from The Euroleague I would like to focus on:
First of all, by all means, an undersized big man and a pure sign of longevity Kyle Hines, this guy is a beast outright. I have watched him since his days at UNCG in college, to now playing for Coach Ettore Messina at Olimpia Milano in the Euroleague (22-23 season).
He carries varying traits of both Modern and Classic big man offensive and defensive skills to say the least.
For a more detailed insight on him check out this bit of work I did on him here:

Played 120 games for UNCG, then begun his pro career at Veroli moved to Bamberg and exploded as a top big, then came the Olympiacos years followed by CSKA and now dominating the game inside and out at Milano he is beyond a force to be reckoned with.
I don’t just admire the guy’s play style but the finesse that he plays the game with is uncanny. He knows what it means to play with momentum and knows how to create and also get his teammates involved and communicates amazingly well.

The other big while initially a bit more classical in upbringing is Vincent Poirier. Begun playing at decent level at Bussy Basket in France, he signed a three year deal that took him to Paris-Levallois where he did some solid work. During the 2016 Summer League Poirier showed off his skill set pretty good. This followed the Baskonia years where he the team during the 18-19 season as the Euroleague’s leading rebounding. He then made a jump to the NBA playing for the Celtics but soon after was traded to Oklahoma followed by a trade to Philly. Back in March 2021 he was traded to the Knicks and waived four days later. This experience did grow his game and he understood that his game needed to be elevated in order to fit the requirements of what was needed from him.
April 2021 Poirier signed a deal with Real Madrid taking him to the 23-24 season.
Both have amazing talent and bring a unique big man look to their teams.
In terms of what a Modern Big does, I recommend that you look into that too.
Working around players, providing them support, also consulting with clubs/teams that are in dire need of assistance in terms of scouting potential talent, its fun to see how organizations are thriving at getting better. The scope of big men as talents on court does not just end with the work they do there, there is a mental side of the game that translates to what they produce as well. While that is a topic for another post, I will leave you with this. A big I really always admired and liked had been Hakeem. His skill set on court was special, no question about it. Not only was he quick to the basket but had a set of foot work that I have not ever seen that has been replicated fully by any of the modern bigs so far.