Export a function

[G]

When I define a func. like

---

define test
    some_command $(1) $(2)
endef

export test

---

and further a func. like

---

define submake
        @                                         \
        for dir in $(2); do                       \
                $(MAKE) $(1) --directory=$${dir}; \
        done
endef

export submake

---

inside a top-makefile and use it down inside a sub-makefile I have the
very same problem like here

https://stackoverflow.com/questions/51319961/export-a-function-in-makefile/51321633#51321633

Passed variables to "imported" func. submake are not passed at all or
are empty.

How do I get around the problem?

Thanks