There are a handful of folks who have taken ClamAV, as suggested above, and productized it. Along with ideas of providing use of other scanning engines. Checkout AWS Marketplace: https://aws.amazon.com/marketplace/search/results?x=0&y=0&searchTerms=s3+antivirus.
You can certainly build it yourself, but these are supported and robust.
Coming from a different question to this one I have to note that currently malware may reside in (from most common to least common):
SSD/HDD flash ROM
NIC/Ethernet flash ROM
Old GPU ROM (modern GPUs ROMs are digitally signed and it's impossible to circumvent it)
The development of malware for any of these ROMs costs astronomical amounts of money, ...
Generically, an EDR-EPP combination such as the ones you describe will assign a threat score based on machine learning, statistical techniques, and a variety of known badness factors, such as enrichments from machine-readable threat intelligence (which can, in turn, also be informed by machine learning, reinforcement learning, and statistical techniques).
Crowdstrike and Sentinel one use EDR or Endpoint Detection and Response, Symantec EEP, Mcafee need a central server to help make the decision of the response. This can hampen decision times (by seconds) but with Malware this can make the difference between a compromise or not.
Symantec uses IOA's and heuristics to detect events.
Crowdstrike uses IOA's IOC's ...