How to deal with disproportional content investment for a ccTLD for a multi-language country,

[Marketing-Omoda]

We have a website for the Belgium market, serving content and products on be/nl (Dutch/Flemmish Belgium) and .be/fr (French Belgium).

However, as a Dutch-based company you can see our primary focus and objective is to serve content to Dutch Belgium rather than French Belgium.

I wonder if, and so, what are the downsides are of only investing in half of the site?
Does it hurt my general .be Google rankings if we put a lot of effort in .be/nl but far less in .be/fr ?

(we used to have a ccTLD .fr as well, but pulled the plug because it wasn't profitable.
our belgium website is profitable for Dutch speaking part of Belgium but now we would like to expand, and enhance rankings. We're investing heavily in (local) brand awareness and partnerships, and content marketing for the Dutch part.

[OlegKorneitchouk]

Make sure they are linked up with hreflang tags which would help search engines determine which pages are their language equivalents.

If you do a lot more promotion of the Dutch content, it will rank better than French pages (assuming equal competition). However, because there is a "these pages are the same but in 2 different languages" hreflang markup on the site, it should help you rank for the French pages as well.