Lemos is an absolutely cracking player and I would love to see him at Everton.
As happy as Las Palmas fans were to get him last year, the expectation from most was that they would lose him in a couple of years to a top club if he carried on developing (If I am honest, I don't think they had us in mind when they said that though!). He is definitely still a developing player and makes mistakes. I would be a little concerned about him coming in as a first choice CB as our fans might turn when he starts passing it around the back and gets caught out if expectations were high. In Las Palmas he would get abuse if he hoofed it, so the change in expectations might be a shock !!
Weirdly enough though he was brought in because Alcaraz was crocked, so may be he wouldn't find the situation that different at all !!!