Erreur de compatibilité php 7.3 wordpress 5.5.1

- Slider Revolution 6.2.22 ne marche pas sur le site après la mise à jour
-- ERROR | "$this" can no longer be used in a plain function or method since PHP 7.1.
- Accordion-toggle ne marche pas (thème du site)
- Plugins erreurs (Page in Widget, MNG Devis plugin sur misure)
-- WARNING | Function create_function() is deprecated since PHP 7.2; Use an anonymous function instead
-- WARNING | Function each() is deprecated since PHP 7.2; Use a foreach loop instead
-- ERROR | Function set_magic_quotes_runtime() is deprecated since PHP 5.3 and removed since PHP 7.0
-- ERROR | Extension 'ereg' is deprecated since PHP 5.3 and removed since PHP 7.0; Use pcre instead
-- ERROR | Function eregi_replace() is deprecated since PHP 5.3 and removed since PHP 7.0; Use preg_replace() instead