Is there any other way to check it than finding the language errors in-game?

You should be able to find the mod zip file under Steam>Workkshop>...
Open it. There you should check localisation>english. In there are the files with all text.

The formatting is as follows:
In esap_I_english.yml You will find all the text entries, in esap_misc_I_english.yml are all the text for modifiers/buildings etc.

Entries typically look like:
ap_esap_bio_cyber_psi_2:0 "Perfect Ascension"
ap_esap_bio_cyber_psi_2_desc:0 "In our mastery of the universe we have ascended to godhood."
ap_esap_bio_cyber_psi_2_tooltip:0 "Latent psionic leaders are no longer twice as likely to get the psionic trait.\nEnables all three Ascension paths."
bio_cyber_psi_2_req_1:0 "$TRIGGER_FAIL$Requires the §Y$ap_esap_bio_cyber_psi$§! Ascension Perk."

were ap_esap_bio_cyber_psi_2 is a tag for the specific perk. the text within " " is what is displayed.
The first is the name of the perk, the second is the description, the third is the effect that is displayed (except for modifiers like +25% Unity output, these are automatically displayed by the game). Finally at the end there is the requirements for the perk.

In addition:
thxt within §Y §! will be displayed yellow, text within §G §! is green. $ap_esap_bio_cyber_psi_2$ will display the string of text that tag is assigned to (in this case Perfect Ascension). Text following a £ will display symbols, £minerals is a mineral symbol, etc.

Alright, found it. My holidays start in a few days. I've got a whole lot of time on my hands so I'll take a look then. Expect a post here within 5 days with my findings :)

Should I just edit the file and save it seperately so I can send it to you? I think that might be easiest.

Good news. I will be leaving on Thursday and won't be able to make any update until the beginning of august. But when I get back I expect to have a look at all the feedback and UI and Balance.

Editing the files and sending to me sounds like a good idea, maybe somehow note which entries are modified and which are not (like exchanging the 0 for a 1, tag:0 "text => tag:1 "text").

Also, if anyone have any ideas for improvement to of names and descriptions to cooler/more fitting stuff I am open. Some of the descriptions/names was a bit rushed. E.g. the "Centralization" perk might have a fitting name to the effect, but it sounds more like a tradition that a top tier Ascension Perk.

Found a spelling error: UIltimate Ascention perk description:
"As we learns..." - "we" is plural, so there should be no "s" in "Learn".

A typo: Technological Perfection, in requirements text: "Must research at leaast on repeatable technology" - "on" instead on "one".

Cheers, thanks for the findings :)

Onwards with the hunt: Reform Academic Structures tech from Secrets of The Universe perk - "Our academic structures are aged an in dire need..." - I assume you wanted to say "and in dire need of reforms".

Same from Reformed Scanning Protocols: "By studying procedures at or scanning..." - I assume it was "at OUR scanning..."

Hi. I made an amateur translation of your fashion into Russian. Can you add a link to the description for convenience?

Yes, can you link the translation?