Missing players in players.json.gz and in transfers.json

[RaphaelleTihon]

I'm trying to gather all the transfer data for specific clubs across many years and for that I'm acquiring the transfers.json data for all the seasons I care about.

I'm first populating the clubs and players sets for all the season I need. I do this by calling
make acquire_local ACQUIRER=transfermarkt-scraper ARGS="--season ${season} --asset clubs"
and then
make acquire_local ACQUIRER=transfermarkt-scraper ARGS="--season ${season} --asset players"

I then run make acquire_local ACQUIRER=transfermarkt-api ARGS="--season ${season}" to populate the transfers.json set for each season.

I'm only interested in transfers that involve teams from the EPL and the Bundesliga. One thing I noticed is that some players are missing from the players table.
This player https://www.transfermarkt.co.uk/nathan/profil/spieler/294798 who came back to chelsea in 2020 after a loan and was sold to another club just after in 2020 is missing from the 2020 players table.

Also this player https://www.transfermarkt.co.uk/kevin-stewart/profil/spieler/200782 who was sold in 2017 from Liverpool to Hull City is missing from the 2017 players table.

As far as I understand, the transfers.json set is populated using the players.json.gz data gathered with the player acquirer? Does it look for all the players in that set and dumps the transfer data in the json?

Also, how does the players table get populated? Is it all the players who played during that year? Could it be that the players above didn't play in a specific season? I don't fully understand yet how the scraper populates this data so I'm probably missing something.

I saw this other issue #156 but I don't think it's related since I'm specifically looking for players/transfers in the EPL.

Some help would be greatly appreciated!
Also if someone knows of an easier way to get all the transfers data for all the EPL clubs for the seasons 1998-2024 it would be really helpful. I'm able to get ~95% but not all because of the missing players mentioned above.

[RaphaelleTihon]

This player might be a great example https://www.transfermarkt.co.uk/john-terry/profil/spieler/3160
He doesn't show up in the 2017 and 2018 player lists but he's there in 2016. So in theory from the 2016 data I can get his 2017 transfers in the transfers data that I acquired for the 2016 season. But this is a bit confusing so I'm wondering why he might be missing in the later years?