So He apparently wiped out every single multiversal singularity with The star saber and some other weapons I forgot. So how powerful is he exactly?
Being one of the 13 and their past track record, I think they fall within "as powerful as the plot calls for." I.E, there probably isn't an upper limit that we're going to see, and if we do, it's likely not going to be entirely satisfying.
I'm sorry to say again any time you make a serious topic asking for information you will not get a serious answer either because nobody cares enough to help or they don't know. Nexus Prime with his own power was able to reverse a star-killing missile, preventing a supernova, then raced back to Cybertron and one-hit KO'ed Omega Doom who himself stated he could survive said star's explosion. We don't have an upper limit of Nexus Prime's power but he is at least star/supernova level in power without special weapons or relics.
I think the problem is that with questions like this there's really nothing anyone can say. The OP has read TFWiki from the sound of it which tells you everything there is to know about this character. The question was not "what did Nexus Prime do in [comic book]" or "could Nexus Prime beat [character]", it's just a totally unbounded question that no one can answer more effectively than the wiki.
His vibrations go up to 11, making him powerful indeed. Oh wait, we aren't talking about Nexus Maximus, are we...
