table interface ( important !! )

Hi all.

On one of my sites I have several technical sheets with lab analysis of our industrial products: since 2019 I have created them with html tables, all formatted with a specific stylesheet (obviously the css is a constant that is always the same for all sheets).
Lab sheets are complex, containing several columns as topics, chemical standards, eference values, etc. etc. and are typically over 40 lines long.
These files, in addition to being many, are also multiplied by three: in the three languages of the site (including one in Far East fonts).

Periodically I have to update the several tables, or add some further for new products.

Until now I’ve done it by integrating and updating everything by hand, table by table inside html, to then delete the old pages and upload all the updated pages …
it is a job that takes too many days, so we are often late in publishing the newest products.

I’m looking for an interface (word, excel or other) to edit published tables or integrate new ones directly from WP admin without having to physically enter the DOM every time …

Possible in WP?

There are several online tools to do this, but I haven’t found one that works for us, because they have their own format and it is not possible to use our custom css.
I’ve seen that there are also some WP plugins, but in that case, for those I’ve found, it’s even worse, because they’re trivial and have their own image and parameters that are useless and harmful to us.

I should build an interface, in my opinion in php, to add to my child theme (if I can’t find something suitable): I ask

1) if this is possible in WP
2) if yes, any procedures and hooks as WP parameters for this (very complex) case

Thank you a lot in advance.

Mauro