List<Some> some = getSome();

// Now each some.other should be asserted by any of multiple conditions.

some.stream.map(Some::getOther).forEach(o -> {
    assertThat(o).satisfiesAnyOf(
        o1 -> assertThat(o1).isNull(),
        o1 -> assertThat(o1).isNotNull().extracting(Other::getId).isEqualTo(x);     
    );
});

assertThat(some)
    .extracting(Some::getOther)
    .allSatisfy(o -> {
        assertThat(o).satisfiesAnyOf(
            o1 -> assertThat(o1).isNull(),
            o1 -> assertThat(o1).isNotNull().extracting(Other::getId).isEqualTo(x);     
        );
    });

List<Some> some = getSome();
assertThat(some)
    .isNotEmpty()
    .extracting(Some::getOther)
    .allSatisfyAnyOf( // or eachSatisfiesAnyOf
        o -> {},
        o -> {}
    );