Now finally after consulting the luametafun and the MetaFun manual I’ve found what I was looking for:

The code:

\startMPcode 
picture p; p := lmt_svg [ filename = "steguppgift.svg", width = 400 ] ;
draw p;
path linje ; linje := (15,-330) -- (280,-90); % adding a missing line in the .svg file
drawarrow linje withcolor black ;
draw thelabel("37°",(160,-330));
draw thelabel("$5,0$m",(150,-160));
\stopMPcode





This was a fun learning experience so thanks again

> 13 feb. 2020 kl. 10:35 skrev Jan-Erik Hägglöf <janerik.hagglof@bahnhof.se>:
> 
> I’ve tested this but it appears outside, not as an layer over the picture.
> 
> \startMPcode 
> draw lmt_svg [
> 	filename = "steguppgift.svg",
> 	height = 5cm,
> 	width = 10cm,
> 	] ;
> label(\sometxt{5,0m},(63.936298,129.563995));
> label(\sometxt{37°},(95.652702,27.367201));	
> \stopMPcode
> 
> Thanks 
> 
> /Janne
>> 12 feb. 2020 kl. 20:10 skrev Hans Hagen <j.hagen@xs4all.nl <mailto:j.hagen@xs4all.nl>>:
>> 
>> On 2/12/2020 6:01 PM, Jan-Erik Hägglöf wrote:
>>> The expected output should be like this, see example in the link below
>>> https://drive.google.com/file/d/13pCuUvNeL7T_Hs7-qrKZclkadcJ7_jVV/view?usp=sharing <https://drive.google.com/file/d/13pCuUvNeL7T_Hs7-qrKZclkadcJ7_jVV/view?usp=sharing>
>>> So that I have a picture so I can change the label text inside according to different needs e.g change from 37° to 41° without reediting it in Inkscape.
>>> A similar properties like latex export picture.pdf_tex which is a function in Inkscape
>>> I investigate the details manual tip you provided, thanks a lot.
>> you might want to peek into the luametafun manual as svg is discussed there, including label stuff
>> 
>> what you can also try (with lmtx) is this (no real interface yet):
>> 
>> \starttext
>> 
>> \hbox\bgroup
>>  \ctxlua{metapost.startsvghashing()}%
>>  \includesvgfile[labels-004.svg]%
>>  \ctxlua{metapost.stopsvghashing()}%
>> \egroup
>> 
>> \stoptext
>> 
>> which should turn your labels into tex, so you can typeset them as tex (so $\\sin(x)$ comes out as math) it's no big deal to add a remap option there but then i'd rather go for symbolic names
>> 
>> Hans
>> 
>> -----------------------------------------------------------------
>>                                          Hans Hagen | PRAGMA ADE
>>              Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
>>       tel: 038 477 53 69 | www.pragma-ade.nl <http://www.pragma-ade.nl/> | www.pragma-pod.nl <http://www.pragma-pod.nl/>
>> -----------------------------------------------------------------
> 
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