IonCube v11 uses AES-256 encryption combined with HMAC signing and dynamic obfuscation. Unlike older versions (v5/v6), v11 does not store the full decryption keys inside the encoded file in a trivial way. A true "decoder" would need to:
No public tool does this reliably for v11. Most "decoders" are actually loaders that run the encoded file but do not output source code. Ioncube Decoder Ic11.x Php 7.4
"Supports all PHP 7.4 structures, decodes obfuscated variables, restores original line breaks, bypasses license checks, and works 100% offline." IonCube v11 uses AES-256 encryption combined with HMAC
Your goal may not be decoding, but simply running the script. Install the free IonCube loader for PHP 7.4: No public tool does this reliably for v11
wget https://downloads.ioncube.com/loader_downloads/ioncube_loaders_lin_x86-64.tar.gz
tar -xzf ioncube_loaders_lin_x86-64.tar.gz
cp ioncube/ioncube_loader_lin_7.4.so /usr/lib/php/20190902/
echo "zend_extension=/usr/lib/php/20190902/ioncube_loader_lin_7.4.so" >> /etc/php/7.4/cli/conf.d/00-ioncube.ini
No decoding required.