Calc user created default template only affects Sheet1

In Calc running on a Windows 7 system, the guides for creating a default template allowed me to set Arial 10 as the default font.

This works for Sheet1. But if an additional sheet is added, Sheet2 is still the original Liberation San 10.
Also, imported CSVs arrive as Liberation Sans 10, not Arial 10.

How can the default template be made to affect additional sheets and imported data?

We just had another thread about the same topic. As there was no answer there, I’m not so confident you will get one here. From very incomplete knowledge: The template is a template for documents, not for objects (this including sheets, drawings, charts …) that may or may not be additionally included. These are created from default templates. I don’t know how to change them.

Just got it for your case. While there isn’t a thing like a sheet style, there are cell styles, of course.
Don’t change the font by direct formatting but modify the ‘Default’ cell style for your template to your needs before saving your template. (Use > ‘Format’ > ‘Styles and Formatting’ -F11, formerly ‘Stylist’. The context menu for the ‘Default’ cell style will offer a ‘Modufy’ option.)
See also: RottenTemplate.ots

{Ceterum censeo: You might consider not to use that … font. If you do, you (e.g.) won’t be able to distinguish an upper case “I” from a lower case “l” without a microscope (or calling the CODE() function).}

[Edit 2021-03-20 about 12:50 UTC]
We just had a new comment by a new user (Welcome!) concerning the topic which might be seen as an alternative answer presenting a workaround for the missing (and impossible) “sheet-styles”.
I should add:
If you want to use a sheet contained in a new Calc document (based on the document template) as a template for additional sheets later, you should keep one such sheet untouched (no editing of it at all), and derive all the actually used sheets of the same kind from it by Move or Copy Sheet.... If not partial hiding of rows/columns is a specific feature, you may then hide all rows and columns to avoid inadvertent editing. In a new sheet created as a copy of the template you can then show the rows and columns again. Regard expectable issues concerning the usage of the SHEETS() functions then.

I have the same problem, cannot open new calc spreadsheet and have desired cell alignment on any sheet other than sheet1. Created template with desired alignment and set it as the default. Then opened a new spreadsheet. Sheet1 had the desired alignment, but NOT SHEET 2 (or 3, or 4…).
Is it possible to have the “default template” control the format of new spreadsheets with more than one sheet?

@raymondvillain: In what way are your observations conflicting with the above answer?

I’m now using Windows 10 64bit, LibreOffice 7. I created a new template setting font type and size, row height and column width. Open a new Calc spreadsheet (if it appears with more than one sheet delete all but one sheet). Next click on the ‘select all’ cell in the top left corner and adjust the font as required, then selected Menu/Format to format the rows and columns. Everything untouched will retain the default Calc spreadsheet style characteristics. I then right clicked on the sheet name and copied the sheet with the name Copy to the end position. Save the file as a template. In use, keep the Copy sheet blank and when you want to add a new sheet copy it with a new name.