LuxTrust S.A. is actually listed as “under supervision” by ILNAS, the Luxembourg public standardisation service, as a trust service provider (TSP) under number 2016/8/001. This attests LuxTrust’s expertise and strict compliance with the most stringent European security norms and standards.
The registry of TSP's supervised by ILNAS is available here.
LuxTrust S.A. is certified according to the standards, the relevant certification can be found here.
The list of services that are eIDAS compliant are available here.