KOD: 〔両墓制で, 墓参(ぼさん)用の墓〕 a “memorial grave”, where prayers and services are held for people actually buried elsewhere.
詣り墓	212	31.5%
参り墓	460	68.5% <- KOD leads with this

I'm a bit uncomfortable with "soul" in this essentially Buddhist context.

@@ -5 +5 @@
-<keb>詣り墓</keb>
+<keb>参り墓</keb>
@@ -8 +8 @@
-<keb>参り墓</keb>
+<keb>詣り墓</keb>
@@ -19 +19 @@
-<gloss g_type="expl">grave for the soul of a deceased person in a two-grave system</gloss>
+<gloss g_type="expl">memorial for prayers and services in a two-grave system</gloss>

Kokugakuin Japan Studies 2023 | Nº 04 (Kokugakuin University)
https://www.kokugakuin.ac.jp/assets/uploads/2023/05/KJS4-full.pdf
2.2.1 Welcoming the Spirits of the Newly Departed
In Nakiri, a double-grave system (ryōbosei 両墓制) was in place from the Edo period
until around the middle of the Meiji period (1868–1912), but as the number of
households increased, the cemetery became too small, and as graves were repeatedly
relocated and the cemetery expanded, a single-grave system (tanbosei 単墓制) was
adopted. However, according to the priest Kaneda Toshiki 金田俊機 of Sen’yūji 仙遊寺,
the traces of the double-grave system can still be seen in the individual family grave plots.
The tombstone carved with the names of the departed that is farthest from the front of
the plot serves as the visitation grave (mairibaka 詣り墓), while the natural stone placed
in front of it serves as the burial grave (umebaka 埋め墓).

Would be happy to have this tweaked.  The meaning of the kanji seemed like they would lend themselves to an obvious literal interpretation("the place you go to commune with the deceased"), so I went looking for one. "visitation grave" seems pretty good to me.

Immediate results suggest that this was a historical practice, perhaps motivated by the desire to separate the corpse from a more hygienic place to visit.  As Japan is now 99+% cremation (it seems), [hist] seems like it should be safe enough for this, and all related terms.

(would have suggested [rare] otherwise)

@@ -14,0 +15 @@
+<xref type="see" seq="2837404">埋め墓</xref>
@@ -16 +17,3 @@
-<gloss>grave for the soul of a deceased person</gloss>
+<misc>&hist;</misc>
+<gloss>visitation grave</gloss>
+<gloss g_type="expl">grave for the soul of a deceased person in a two-grave system</gloss>

daij　nikk