Regex & Python: переводите с помощью beautifulsoup и googletrans только те HTML-теги, которые содержат определенные ключевые слова.

'''
# pip install googletrans==4.0.0rc1
def read_file(_path):
    with open(_path, "r", encoding="utf-8") as f:
        _html_str = f.read()
        return _html_str
def write_file(_path, _str):
    with open(_path, "w", encoding="utf-8") as f:
        f.write(_str)
'''
from bs4 import BeautifulSoup
from bs4.formatter import HTMLFormatter
from googletrans import Translator
import requests
translator = Translator()
class UnsortedAttributes(HTMLFormatter):
   def attributes(self, tag):
       for k, v in tag.attrs.items():
           yield k, v
files_from_folder = r"c:\\Folder3"
use_translate_folder = True
destination_language = 'ro'
extension_file = ".html"
import os
directory = os.fsencode(files_from_folder)
def recursively_translate(node):
   for x in range(len(node.contents)):
       if isinstance(node.contents[x], str):
           if node.contents[x].strip() != '':
               try:
                   node.contents[x].replaceWith(translator.translate(node.contents[x], dest=destination_language).text)
               except:
                   pass
       elif node.contents[x] != None:
           recursively_translate(node.contents[x])
amount = 1
for file in os.listdir(directory):
   filename = os.fsdecode(file)
   print(filename)
   if filename == 'y_key_e479323ce281e459.html' or filename == 'directory.html':
       continue
   if filename.endswith(extension_file):
       with open(os.path.join(files_from_folder, filename), encoding='utf-8') as html:
           soup = BeautifulSoup('<pre>' + html.read() + '</pre>', 'html.parser')
           for title in soup.findAll('title'):
               recursively_translate(title)
           for meta in soup.findAll('meta', {'name':'description'}):
               try:
                   meta['content'] = translator.translate(meta['content'], dest=destination_language).text
               except:
                   pass
           for h1 in soup.findAll('h1', {'itemprop':'name'}, class_='den_articol'):
               if begin_comment < str(soup).index(str(h1)) < end_comment:
                   recursively_translate(h1)
           for p in soup.findAll('p', class_='text_obisnuit'):
               if begin_comment < str(soup).index(str(p)) < end_comment:
                   recursively_translate(p)
           for p in soup.findAll('p', class_='text_obisnuit2'):
                   recursively_translate(p)
           for p in soup.findAll('p', class_='NOU'):
               recursively_translate(p)
           for span in soup.findAll('span', class_='text_obisnuit2'):
               if begin_comment < str(soup).index(str(span)) < end_comment:
                   recursively_translate(span)
           for li in soup.findAll('li', class_='text_obisnuit'):
               if begin_comment < str(soup).index(str(li)) < end_comment:
                   recursively_translate(li)
           for a in soup.findAll('a', class_='linkMare'):
               if begin_comment < str(soup).index(str(a)) < end_comment:
                   recursively_translate(a)
           for h4 in soup.findAll('h4', class_='text_obisnuit2'):
               if begin_comment < str(soup).index(str(h4)) < end_comment:
                   recursively_translate(h4)
           for h5 in soup.findAll('h5', class_='text_obisnuit2'):
               if begin_comment < str(soup).index(str(h5)) < end_comment:
                   recursively_translate(h5)
           for h1 in soup.findAll('h1', {'itemprop':'name'}, class_='den_webinar'):
               if begin_comment < str(soup).index(str(h1)) < end_comment:
                   recursively_translate(h1)
           for h3 in soup.findAll('h3', class_='font-weight-normal'):
               if begin_comment < str(soup).index(str(h3)) < end_comment:
                   recursively_translate(h3)
           for h3 in soup.findAll('h3', class_='font-weight-normal'):
               if begin_comment < str(soup).index(str(h3)) < end_comment:
                   recursively_translate(h3)
           for span in soup.findAll('span', class_='online'):
               begin_comment = str(soup).index('<!-- post -->')
               end_comment = str(soup).index('<!-- ARTICOL START -->')
               if begin_comment < str(soup).index(str(span)) < end_comment:
                   recursively_translate(span)
           for p in soup.findAll('p', class_='mb-40px'):
               if begin_comment < str(soup).index(str(p)) < end_comment:
                   recursively_translate(p)
           for p in soup.findAll('p', class_='mb-35px color-grey line-height-25px'):
               if begin_comment < str(soup).index(str(p)) < end_comment:
                   recursively_translate(p)
       print(f'{filename} translated ({amount})')
       amount += 1
       soup = soup.encode(formatter=UnsortedAttributes()).decode('utf-8')
       new_filename = f'{filename.split(".")[0]}_{destination_language}.html'
       if use_translate_folder:
           try:
               with open(os.path.join(files_from_folder+r'\translated', new_filename), 'w', encoding='utf-8') as new_html:
                   new_html.write(soup[5:-6])
           except:
               os.mkdir(files_from_folder+r'\translated')
               with open(os.path.join(files_from_folder+r'\translated', new_filename), 'w', encoding='utf-8') as new_html:
                   new_html.write(soup[5:-6])
       else:
           with open(os.path.join(files_from_folder, new_filename), 'w', encoding='utf-8') as html:
               html.write(soup[5:-6])