That's some thing I looked into a bit a few months ago...
Thanks! This is a helpful post because it means I did not miss something when I was looking into this too. Like yourself I went back to CM 01/02 with updated teams but no score editor was to be found so I gave up.
As for PES 2018 - I played up until the 2nd week of the world cup and was having a good time because I was winning with my England team in the online national cup.... but how konami showed me their incompetence was that for entry all you had to do was change your team emblem. Lol. Such a waste.
At about that time I started looking more into ML and reading about it on forums. Reading about the transfer issues makes it another wasted opportunity. These years I thought I'd have ML to fall back on if I ever got fed up of grinding in MyClub. I also used to watch people post their journeys through a season ---- no offence but they must be either funded by konami, seeking clickbait/youtube hits or genuinely interested but just plain naive to the script and longterm pointlessness.
You mention that ML works in 2019 .... I hope you are right and if ppl are singing its praises I will get PES 2019 when it is heavily discounted.
Regarding your interest in the world cup and pes in general, I give you my take on things. Although I support spurs, I stopped watching football last year (I think the move to Wembley stadium just made last year and this year a bit meh and pointless). I don't have any sports channels. So for the world cup I watched all the games. Some were dry and I found myself doing other things during them but overall this was a great world cup for me (also England did well - beating a frustrated Columbia was good). Best games were Spain v Portugal; Belgium v Japan and Germany v Sweden. VAR worked well except in the final was poorly utilised by ref and, in my eyes, Croatia won the WC.
What I'm saying is that I think I enjoyed the WC more because I wasn't watching football regularly. I think the same goes for PES. SO my plan this year is not to touch anything PES 2019 and dip in and out of PES 2018 and past PES'. I have set up an ML on 2014 and 2018 recently. There is a nice contrast (retro-ish vs modern) plus a few players in 2014 appear in 2018 (like, I think Niellender - I play my MLs as Cardiff City with PES starting lineup; full manual, 20 mins, professional; maybe one game daily, if that).
The other reason I post is to push the idea that PES 2019 is the fans opportunity to tell konami to start addressing issues or get the hell out of my game library. PESfan forum was acrrying a lot of negativity - its conspiracy theory but I think that had a lot to do with its shut down. The thing is, looking at this forum and reading what people are looking for in PES 2019, I hope konami will start to get the picture (of the lack of richness in their product)