ModbusBB
Modbus master, simulator & CLI for Windows + 24/7 SCADA Cloud gateway
...Offline buffer, team members. $59 first year, then $89/year, lifetime licence included. Video: https://youtu.be/Ki3S1B9l5v8
Free 30-day trial (15-minute sessions). $10 lifetime licence, up to 3 PCs, free updates.
By Max Energic Apps. Docs: https://modbus.maxenergic.com/docs.html