Since "2021" implies a specific era of modding, you need to look for archives or reputable forums.
Option A: Aussieler.de (German Forum - Best Source) This is the hub for high-quality OMSI mods.
Option B: OMSI WebDisk This is a massive repository of mods. iveco crossway le omsi 2 download 2021
Option C: Simulators Worldwide (STS / Matrix) In 2021, a version was circulating from the "Simulators" team. This version is often high quality but may require specific HOF files.
Selecting the bus:
Once installed, when choosing a bus for a map, look for: Since "2021" implies a specific era of modding,
Important controls for the 2021 version:
Absolutely—with caveats.
If you want the 2021 experience rather than the exact file, download the latest version of the Crossway LE and then apply a "Retro Sound Pack" or "2021 UI Skin" available on forums.