Inserting image from SVG file, custom frame style gets overwritten

Version: 7.6.4.1 (X86_64) / LibreOffice Community
Build ID: 60(Build:1)
CPU threads: 2; OS: Linux 6.1; UI render: default; VCL: gtk3
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7.6.4-1
Calc: threaded

.odt document

SVG files were produced in Python matplotlib by exporting to svg.
In odt file custom frame style is defined to assign to images inserted from SVG files.
Used custom frame style is grandchild of ‘Graphics’ Writer stock-style; at the midpoint of this
short chain of frame styles one other custom frame style; hence the chain of inheritance looks
like this ‘Graphics’ > custom frame style > yet other custom frame style.
In practicing only this manner: inserting SVG images by embedding into odt instead of linking image inserted to source SVG file.

Procedure:

  • Insert > Image…
  • In Open File dialog select the SVG file
  • one click on OK to confirm
  • back to document with image inserted
  • select image/ make it to current object selected
  • assign custom frame style to image
  • in this step the point got reached where problem starts be observable

Problem:
Image frame doesn’t adhere to frame style definition. Author uses visual check of image frame size in order to verify if all is as expected - frame style has remarkable frame size - image’s frame size deviates from that one in used custom frame style.
In order to avoid running on troubles the document author refrains from modifying image frame properties in other manner than assigning a frame style to image, this unfortunately does not help.
In course of the search of possible reasons one inspected the image frame Properties…
If to inspect setting in Position and Size tab several settings deviate from those set in used custom frame style. Among others Width and Height, the Anchor. Latter one is To character while it should be As character.
Custom frame style uses As character as anchor.

I wonder what is the reason of this deviation.
I wonder why is image frame not adhering to assigned frame style.
Q.1 How should further searching for reason look like?

Few additional questions:
Q.2 Will importing original SVG to Draw document than exporting back to vector graphic file improve the compatibility on Writer side?
Q.3 If yes, which vector format should Draw export to in order to improve the compatibility in mind?
Q.4 Will exporting graphic from Python matplotlib to other vector format increase the chance for progressing without troubles?

… if you post a minimum viable sample, both odt and svg file, that would make helping you easier