Summary
Nwaba has at times been a rotation-level wing, but has struggled to stay healthy in recent seasons. He only played in 30 games in '20-'21 due to a wrist injury, and only played in 43 games in '21-'22 at a pretty low 12 minutes per game. 

Nwaba hasn't proven to be a threat from outside, as he's just a 32% 3-point shooter for his career on pretty low volume. However, he can attack off the dribble and has generally finished pretty decently at the rim. He isn't a ball-stopper and can make the right reads on offense. He attacks the offensive glass hard and has put up elite offensive rebounding rates for his positions.

Defensively, Nwaba is a strong wing that can guard multiple positions. He rebounds well and gets a high rate of steals and blocks. He's 6'5" but plays bigger than that, and has the ability to guard bigger forwards. 

In recent seasons, and really for the vast majority of his career, Nwaba has played on bad teams. I think they he could contribute as a solid 8th-9th man, and would be interested to see him playing for a team that is in contention, but teams apparently don't agree with me as he remained unsigned for the entire '22-'23 season.
 
Cap Considerations
Nwaba was waived by the Thunder after being traded away from Houston prior to the season, and has yet to sign with another team. 

Teams will have multiple ways to sign Nwaba as even teams without cap space could possibly use any of the Non-Taxpayer MLE, Taxpayer MLE, or even the Room MLE or Bi-Annual Exception to sign him. It's also likely that Nwaba only gets minimum offers, and he may not even get fully-guaranteed offers.