Hi thank you for the response guys.
I ended up buying this. https://www.amazon.com/Sony-NPAMQZ1K-Multi-Battery-Adaptor/dp/B06ZZ3KH4W/ref=sr_1_3?keywords=sony+multi+charger&qid=1556744157&s=gateway&sr=8-3
It comes with 2 batteries, so now I only need to buy 1 more battery. It charges 4 batteries, and can be used as a large battery pack . You can also mount it on a gimbal . Its fantastic so far!
I remember when ISS first came out there was a lot of talk about it having to be turned off when the camera was on a tripod. Perhaps that was true in the beginning. By the time I started buying Nikon "VR" lenses, however, turning ISS off for tripod mounting was being disputed by many photographers, and I found that it did not seem to matter.
So when I decided to change from Nikon to Sony, with the debut of the A7Rm3, I noticed that Sony recommends turning ISS off when using a tripod. Oh my, here we go again.
As a result, I decided to photograph the NBS 1952 resolution targets that I had used years ago with film cameras. This target provides resolution tests down to 80 lines per mm. I set up enough targets to provide checking the image center, all four corners, and the image edges. Test were run on the FE 16-35 F:2.8 GM, the FE 24-105 F:4 G OSS, and the FE 100-400 F:4.5-F5.6 GM OSS. All three lenses were tested at minimum, medium and maximum focal length. Exposure times were typically 1/10 to 1/5 second. The F stop was F:8 for the two shorter lenses and F:11 for the 100-400. The self timer was used on the 100-400 to ensure that there was no shaking when pressing the shutter release.
The images were shot in RAW and processed in Photoshop with Camera Raw default sharpening. I then viewed the targets, side by side, at 200%. The end result was that I could NOT SEE any difference for ISS ON or ISS OFF when tripod mounted. Hence, I will not worry about this anymore.
As a side note, I was pleased to see that both of the GM lenses were able to produce 80 lines/mm resolution at the center and all corners. The 24-120 G F:4 was not quite as good on the corners and the left edge was noticeably blurred, which would indicate a defect of some sort. I will return this lens for a replacement.