It seems to be not that complicated at all …
First the search string for Google, with surrounding of multiple words with double quotation marks (you can paste all URIs into Safari to check):
Then I click on the first result:
Note the found document: %3A52002XC0515%2803%29, which looks complicated but uses actually URI (or percentage) encoding to handle the colon and brackets.
Decode this string with Keyboard Maestro’s function:
And you get: :52002XC0515(03)
Which you can combine with the leading string https://eur-lex.europa.eu/legal-content/ES-IT/TXT/?uri=CELEX
And the trailing string &from=ES to get your desired view:
Can you test this procedures in 3 examples for each of your language combinations and directions?
Here's the KM function:
With this nice macro you can get the first n results from Google in a collection. You can use this collection to create n bilingual views for your EUR-LEX search results.
Wonderful! This is going to save me eons of time. Thank you!