One website i rely on a lot is this one...
http://www.footballsquads.co.uk/squads.htm
Check out the archive section as it goes back quite a number of years.
When there's multiple sources, the best way is to compare players on pictures, with 2 or 3 others well known players (often older).
I will talk about current teams, but it's not always reliable, South African for example is full of errors. One player is 198cm from some source, 179 for some others. So... I founded a picture with the whole team, based on number from soccerway or another website on a game played.
He's 198 in both FM, Fifa, and PES. But in reality.... He's 179cm or close to it
Take a look, that's the player named "T. HLATSHWAYO", you can see on him on this match and the picture before.
https://us.soccerway.com/matches/2018/11/20/world/friendlies/south-africa/paraguay/2933491/
He's Number 14... The number 2 (smaller) is MOKOENA, 176cm. The number 6 and the number 9 MOTHIBA, 181cm are the most secure regarding club they played before so better information. Number 9 is 181cm.
The GK is 183-184 varies from source, but it's accurate, i compared on others pics.
Number 6 for example is also wrong : they list him as 185. But he's a tiny bit smaller than the 181cm player, and the same height approximatively as the first player i was talking about "T. HLATSHWAYO". On this picture he looks a tiny bit taller but that's an illusion, he's a tiny bit smaller or got +- the same height (i gived him (177-178cm)
And finally, on that kind of picture... TAKE A LOOK AT THE FEET > Number 13 (don't remember his name) is listed as 180cm and it fits with all pictures i saw.
EDIT/ But he's also listed 188cm elsewhere... So if you just look at the higher their head reach, you can be totally wrong.
He looks taller than everyone, but (and it happens a lot on that kind of pictures)
he's on the point of his feet 
About weight, i check about his body build, and gives an approximation when it's not available, it's pretty variable, a player can gain or loose 5 kg in a short amount of time. Some players where 180/75kg and now they're like 85kg... I try to check most recent pics. As both height and weight have an influence on Konami's standards stats.
Also, San Marino wasn't that hard to found, but some others teams, i gotted to made plenty of Height/Weight estimation.
I'm upper busy, and i'm less free since i'm with PESuniverse but also wants to send my work to Konami now, i've done something reallly professionnal with explanations and all... Full time job, you got sometimes to check on social network and being passionnate, having "the eye" too without trowing me flowers.
I also checked about wrong foot for example. It's not all about Hgt/Wgt.
I will perhaps send you my research, because i've done litterally every National teams... But for now on, i can't for the reasons i've given
But i gives you tips if you want to create a small team. It's a bit harder without having at least one, two, or three "landmarks" players to base on. And another important thing if you do that DON'T try to be too rigid about height, you can gain 1cm a day, loose it another day etc.
Personnally i'm according 3cm maximum error range for very tall players (190+), but for average 2cm.
I'm talking about a very precise process, but you don't have to do that. the first goal is to get player who are closer to 170cm, 175cm, 180cm, 190 or 165 etc. to be at least "ressembling" overally
BTW players between 165-166cm and i would say 182-183cm are easier to got them more precise. It became difficult to judge when they're above or below those values.
). So far, so good. I put Ajax and Werder Bremen in Div 2 with me to make it more interesting, and to keep these good teams in the game.
).
. Great immersion.