These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.65 s (backtrack: 0/20).

[ebuild   R    ] sys-libs/zlib-1.3.2-r1:0/1::gentoo  USE="minizip* -static-libs -verify-sig" 1290 KiB
[ebuild  N     ] virtual/minizip-1.3.1:0/1::gentoo  USE="-static-libs" 0 KiB
[ebuild  N     ] sci-geosciences/readosm-1.1.0a::gentoo  1074 KiB
[ebuild  N     ] dev-libs/freexl-2.0.0-r1::gentoo  969 KiB
[ebuild  N     ] sci-libs/geos-3.14.1::gentoo  USE="-doc -test" 6850 KiB
[ebuild  N     ] sci-libs/proj-9.7.0:0/9::gentoo  USE="tiff -curl -test" 779149 KiB
[ebuild  N     ] dev-db/spatialite-5.1.0-r3::gentoo  USE="geos iconv proj xls -rttopo -test" 6365 KiB
[ebuild  N     ] dev-db/spatialite-tools-5.0.1-r2::gentoo  USE="readline" 565 KiB

Total: 8 packages (7 new, 1 reinstall), Size of downloads: 796259 KiB

The following USE changes are necessary to proceed:
 (see "package.use" in the portage(5) man page for more details)
# required by virtual/minizip-1.3.1::gentoo[-static-libs]
# required by dev-db/spatialite-5.1.0-r3::gentoo
# required by dev-db/spatialite-tools-5.0.1-r2::gentoo
# required by =dev-db/spatialite-tools-5.0.1-r2 (argument)
>=sys-libs/zlib-1.3.2-r1 minizip