I decided this year that I would do something that I've toyed with doing for a number of years - I would sit down and figure out how many players in NPB had cards this season and how many did not. To make life a bit easier for myself I limited myself to seeing who appeared in the BBM and Calbee "flagship" sets (1st Version and 2nd Version for BBM and the Series One and Two for Calbee) as well as the BBM team sets (the 81 card pack based sets, not the smaller box sets). I didn't include any of the Epoch sets since they didn't do any large scale sets. (From what I could see there weren't any players who appeared in an Epoch set but not in a BBM set.)
Here's some numbers on what I figured out - there were 924 players who appeared on an NPB roster this season. 88 of these players were ikusei players. From what I can tell there were 75 players who did not have cards this season.
There were 654 players who made at least one appearance at the ichi-gun level. 15 of these players did not have a card in one of the sets that I mentioned although six of those appeared in the BBM Fusion set (four of them also appeared in BBM's Genesis set) - Wily Mo Pena and Roel Santos of the Marines, Livan Moinelo of the Hawks, Xavier Batista of the Carp, Chris Marrero of the Buffaloes and Carlos Rivero of the Swallows. This leaves nine ichi-gun players who did not have any NPB cards at all this season. Four of these are foreign players - Jason Rogers of the Tigers, Yadir Drake of the Fighters, Stephen Fife of the Lions and Josh Corrales of the Eagles. The other five are all ikusei players who were moved to their team's 70-man roster during the season - Taturo Iwasaki of the Dragons, Alejandro Mejia of the Carp, Shogo Kimura of the Lions and Ryuta Konno and Chia-Hai Sung of the Eagles.
Additionally there were five players who only played at the ni-gun level who also did not appear on any cards this season. All of these players were ikusei players who were registered to the 70 man roster during the season. They are Naoto Nishida of the Tigers, Takumaru Yaoita of the Eagles and Makoto Aoyama, Daiki Masuda and Takaya Tanaka of the Giants.
BBM hasn't included any ikusei players in their pack based team sets for the last few years so the only ikusei players who have cards this year are the ones who were taken in last fall's draft and therefore appeared in BBM's Rookie Edition set last winter. There are 27 ikusei players who had cards in Rookie Edition leaving another 61 who had no cards at all in 2017.
In addition, there were seven players who were traded during the season. Only three of these players appear on a card with the team they were traded to - Keisuke Tanimoto of the Dragons, Luis Mendoza of the Tigers and Toshiki Kurobane of the Fighters. All three of these cards are in the BBM Fusion set. The other four players are Toshihiro Sugiura of the Fighters, Luis Cruz of the Eagles, Shogo Yagi of the Swallows and Edwin Escobar of the Baystars.
I do want to point out that I don't have the Fusion set in hand yet so the cards in it are not in my database. I've simply added the nine "1st Version Update" cards to my list. It's possible (although I don't think it's likely) that some of the players that are missing have "regular" cards in the Fusion set.
I've embedded the spreadsheet that I put together to figure all this out. I did an SQL query to get the list of the 2017 cards I had which I then manually went through and rearranged to the current format. (If I do this again next year I'll probably write a Java program to do that part.) I then compared the list of players for each team with the rosters on NPB's website (which luckily haven't been updated for 2018 yet). I included in the listing the manager for each team and any coaches that appeared in the team sets (which was only Masayuki Kakefu of the Tigers).
There was only one team for which every player this season had a card - the Chiba Lotte Marines. Their only two ikusei players (Shota Sugawara and Yoshizumi Yasue) were in BBM's Rookie Edition set and their only late signing foreign players were Pena and Santos who were in both the BBM Genesis and the BBM Fusion sets.
A couple of notes about this sheet - I only listed sets in the "Other Sets" column if the player did not appear in a "flagship" or BBM team set. So for example since Shohei Ohtani appeared in BBM's 1st and 2nd Version sets as well as their Fighters team set and Calbee Series One, I didn't also list him as appearing in Genesis and Fusion. The contents of the "Notes" column was taken pretty much verbatim from the rosters on the NPB website. I didn't include notes for players who were released or retired as it wasn't pertinent to what I was trying to accomplish.
I hope all of this makes sense. I've been working on this for more than a week.