Get all variants from multiple products

Question

I need to get a list of variants from multiple products, but in a way that allows us to show the results in Craft's handy {% paginate %} tags.

So far we have this less-than-appealing markup:

{% set firstProduct  = craft.products.relatedTo(category).one() %}
{% set results = craft.variants({product: firstProduct}) %}

{% set products  = craft.products.relatedTo(category).all() %}

{% for product in products %}
    {% set results = results|merge(craft.variants({product: product})) %}
{% endfor %}

However, because we're using merge it's turning our ElementCriteriaModel into an Array. Is there a way to use the {{ craft.variants({product: product}) }} tag and pass it multiple products?

(Craft3 and Commerce2)

Thanks

EDIT: Final markup that ended up working:

{# All products within this category #}
{% set products = craft.products.relatedTo(category).all() %}

{# Empty variant id array #}
{% set variantIds = [] %}

{# Populating variant id array #}
{% for product in products %}
    {% set variantIds = variantIds|merge(craft.variants({product: product}).ids()) %}
{% endfor %}

{# Get all variants from the variant id array #}
{% set results = craft.variants.id(variantIds).orderBy('title asc') %}

Answer 1

The "variant" method can receive multiple ids using the following: craft.variants().id([1,2,3]).

Following that, you can easily populate an array while looping through your (specific) products, and then use that array to fetch the variants.

Official documentation